2012年3月25日 星期日
Hobbywing XERUN SCT PRO Sensored ESC (BU) For Short Course Truck
2012年3月13日 星期二
DAILY MAINTENANCE of your RC Model
Buy more RC Model Toy at www.hobbyhot.com
I To keep your car at optimum performance, daily maintenance is important. This will also help discover any hidden problem areas. Without this daily care, your car’s performance can deteriorate rapidly. Keep it in the best possible condition at all times.
1. MAINTEIY GE OF R/C UNITS
Your radio control receiver, transmitter, servos and amplifier boosted speed control are precision electronic instruments. Clean these components after use, especially the connector sockets on the receiver, as they collect dust. Remove plugs and clean the sockets using a soft bristled brush.
*If a malfunction occurs with your radio, do not attempt to dismantle and repair by yourself. No user-serviceable parts are inside. Send to the manufacturer or service station for repair.
IF THE RECEIVER ANTEN- M NA CABLE BREAKS
If the antenna breaks at its base, do not dismantle the receiver. Send it to the manufacturer for repair. If the insulation is worn, cover the bare wire using vinyl tape. If left uncovered, accidental contact with metal parts will cause radio interference and loss of control of the model.
2. MAINTENANCE OF ELECTRIC COMPONENTS
Electrical components play a vital role in models, whether battery powered or glow engined. Make sure to check them prior to and after each use.
ELECTRIC CABLES
Electrical wire/cables can withstand some degree of stretch; however, if excessively pulled, they can break or become detached from a solder joint. Insulation will wear off if rubbed against the ground or a car’s rotating part while running. Special attention should be paid to motor/battery cables on Ni-Cd battery powered models, due to the enormous amount of current that flows in these circuits. Any short circuit can cause a fire or serious burns.
CONNECTORS
Connectors can become loose and develop bad contact following repeated use. Crimp the tubular contact points using the tip of a screwdriver to maintain firm contact in the
plug.
MECHANICAL SPEED CONTROL
A mechanical speed control passes large currents and its metal contacts repeatedly rub against each other during operation. Metal wears more rapidly than you expect, and this causes poor electrical contact, scorching of points, and sparking. Scorched contact points can be cleaned using fine abrasive paper, but if badly worn, the entire speed control unit should be replaced. Keep and sand away from metal contacts, and periodically apply switch lubricant for smooth movement and good contact.
3. MAINTENANCE OF ELECTRIC MOTORS
The electric motor is the vital component in electrically powered models, and it will wear out following extended use. Keep in mind that stiff meshing gears, hindrance of wheel/shaft rotation and running the model in grass or dry sand imposes great stress on the motor and can result in motor burn out.
REPLACING BRUSHES AND ROTORS
A major reason for reduced motor performance is worn brushes and/or damaged commutator. High performance motors can be disassembled for cleaning, and new brushes and rotors are available for replacement. In these cases, motor performance can be restored to like new.
NOISE SUPPRESSING CONDENSERS
Electric motors generate electromagnetic noise during operation, so electric motors are equipped with noise suppressing condensers to filter out this noise. A standard 540 size motor houses its condenser inside the case so there is little possibility it will come off; however, some high performance motors have their condenser attached outside on the end bell. Check that it is firmly attached and re-solder if necessary.
4. MAINTENANCE OF CHASSIS COMPONENTS
Properly assembled and operating chassis mechanics are the basis for optimum performance of an car. Keep your car in peak condition by constantly inspecting and maintaining it.
1. LOOSENED OR DAMAGED SCREWS & NUTSScrews and nuts can become loosened from vibration while running. They can even become bent and distorted from a collision. Tighten screws and nuts and replace those that are bent, cracked or damaged. Stripped screws and nuts must also be replaced.
2. GEARS AND JOINTSEven durable plastic or metal, gears and joints are subject to wear because they are always in motion during use. Proper lubrication reduces friction, and helps prolong the life of these parts. If gears are exposed, foreign objects such as sand and debris get between the teeth, damaging the gears. Check and replace any damaged or worn gears grid joints immediately.
3. BENT SHAFTS
Shafts can become bent following a collision. Even a slight bend in an axle or propeller shaft can cause vibration and unstableness of the car. Periodically remove them from the car to check if they are straight. Bends can be found by rolling the shaft slowly along a flat surface.
4. DAMAGED OR DISTORTED FRAME/CHASSIS
The frame/chassis is the backbone of your car, and made to withstand extreme stress. However, it can become damaged or distorted following repeated hard collisions. Check for any distortion by placing the model on a flat surface and gradually raising it from the surface. If a wheel on either side leaves the surface sooner than the other, chassis deformation or an incorrect suspension setting can be suspected. A slight distortion can be corrected by twisting the chassis in the opposite direction, but it is best to replace it with a new one as soon as possible. Check screw holes on the frame/chassis for cracks or damage.
5 & 6. SUSPENSION COMPONENTS
Suspension arms and pivots are subject to damage during collisions. Check and replace deformed arms, bent shafts, etc. Lubricate all suspension pivot points for smooth operation.
7. STEERING LINKAGE
Because a steering servo saver is constantly receiving external shocks from direct contact with the steering mechanics, it will gradually deteriorate with prolonged use. Plastic ball sockets used at tie-rod ends can become loose after repeated attachment and removal. Periodic replacement of these parts will be required. In due course, replace any damaged components.
8. CHECKING DRIVE BELTDrive belt tension has to be checked periodically. Drive belt can be easily adjusted by changing pulley position. In addition, change it when damaged and clean it if it becomes dirty.
BODY REPAIRS
Even a slightly damaged or cracked body shell will worsen beyond repair due to running vibrations. Styrene bodies can be repaired using plastic cement or instant glues (Cyanoacrylates). Apply sheet styrene from the inside for reinforcement. Polycarbonate (Lexan) body shells cannot be repaired with cements, so use cloth tape or fiberglass reinforced tape for repairs. Polycarbonate sheet, cut from a body shell can be used as reinforcement under the cloth tape.
LONG TERM STORAGE
Remove all batteries from model. If the car is to be stored for an extended period, remove the wheels, or put the model on a stand with the wheels clear of the ground. This prevents the tires from deforming.
Copyright from TAMIYA RADIO CONTROL GUIDE BOOK 2005
Buy more RC Model Toy at www.hobbyhot.com
I To keep your car at optimum performance, daily maintenance is important. This will also help discover any hidden problem areas. Without this daily care, your car’s performance can deteriorate rapidly. Keep it in the best possible condition at all times.
1. MAINTEIY GE OF R/C UNITS
Your radio control receiver, transmitter, servos and amplifier boosted speed control are precision electronic instruments. Clean these components after use, especially the connector sockets on the receiver, as they collect dust. Remove plugs and clean the sockets using a soft bristled brush.
*If a malfunction occurs with your radio, do not attempt to dismantle and repair by yourself. No user-serviceable parts are inside. Send to the manufacturer or service station for repair.
IF THE RECEIVER ANTEN- M NA CABLE BREAKS
If the antenna breaks at its base, do not dismantle the receiver. Send it to the manufacturer for repair. If the insulation is worn, cover the bare wire using vinyl tape. If left uncovered, accidental contact with metal parts will cause radio interference and loss of control of the model.
2. MAINTENANCE OF ELECTRIC COMPONENTS
Electrical components play a vital role in models, whether battery powered or glow engined. Make sure to check them prior to and after each use.
ELECTRIC CABLES
Electrical wire/cables can withstand some degree of stretch; however, if excessively pulled, they can break or become detached from a solder joint. Insulation will wear off if rubbed against the ground or a car’s rotating part while running. Special attention should be paid to motor/battery cables on Ni-Cd battery powered models, due to the enormous amount of current that flows in these circuits. Any short circuit can cause a fire or serious burns.
CONNECTORS
Connectors can become loose and develop bad contact following repeated use. Crimp the tubular contact points using the tip of a screwdriver to maintain firm contact in the
plug.
MECHANICAL SPEED CONTROL
A mechanical speed control passes large currents and its metal contacts repeatedly rub against each other during operation. Metal wears more rapidly than you expect, and this causes poor electrical contact, scorching of points, and sparking. Scorched contact points can be cleaned using fine abrasive paper, but if badly worn, the entire speed control unit should be replaced. Keep and sand away from metal contacts, and periodically apply switch lubricant for smooth movement and good contact.
3. MAINTENANCE OF ELECTRIC MOTORS
The electric motor is the vital component in electrically powered models, and it will wear out following extended use. Keep in mind that stiff meshing gears, hindrance of wheel/shaft rotation and running the model in grass or dry sand imposes great stress on the motor and can result in motor burn out.
REPLACING BRUSHES AND ROTORS
A major reason for reduced motor performance is worn brushes and/or damaged commutator. High performance motors can be disassembled for cleaning, and new brushes and rotors are available for replacement. In these cases, motor performance can be restored to like new.
NOISE SUPPRESSING CONDENSERS
Electric motors generate electromagnetic noise during operation, so electric motors are equipped with noise suppressing condensers to filter out this noise. A standard 540 size motor houses its condenser inside the case so there is little possibility it will come off; however, some high performance motors have their condenser attached outside on the end bell. Check that it is firmly attached and re-solder if necessary.
4. MAINTENANCE OF CHASSIS COMPONENTS
Properly assembled and operating chassis mechanics are the basis for optimum performance of an car. Keep your car in peak condition by constantly inspecting and maintaining it.
1. LOOSENED OR DAMAGED SCREWS & NUTSScrews and nuts can become loosened from vibration while running. They can even become bent and distorted from a collision. Tighten screws and nuts and replace those that are bent, cracked or damaged. Stripped screws and nuts must also be replaced.
2. GEARS AND JOINTSEven durable plastic or metal, gears and joints are subject to wear because they are always in motion during use. Proper lubrication reduces friction, and helps prolong the life of these parts. If gears are exposed, foreign objects such as sand and debris get between the teeth, damaging the gears. Check and replace any damaged or worn gears grid joints immediately.
3. BENT SHAFTS
Shafts can become bent following a collision. Even a slight bend in an axle or propeller shaft can cause vibration and unstableness of the car. Periodically remove them from the car to check if they are straight. Bends can be found by rolling the shaft slowly along a flat surface.
4. DAMAGED OR DISTORTED FRAME/CHASSIS
The frame/chassis is the backbone of your car, and made to withstand extreme stress. However, it can become damaged or distorted following repeated hard collisions. Check for any distortion by placing the model on a flat surface and gradually raising it from the surface. If a wheel on either side leaves the surface sooner than the other, chassis deformation or an incorrect suspension setting can be suspected. A slight distortion can be corrected by twisting the chassis in the opposite direction, but it is best to replace it with a new one as soon as possible. Check screw holes on the frame/chassis for cracks or damage.
5 & 6. SUSPENSION COMPONENTS
Suspension arms and pivots are subject to damage during collisions. Check and replace deformed arms, bent shafts, etc. Lubricate all suspension pivot points for smooth operation.
7. STEERING LINKAGE
Because a steering servo saver is constantly receiving external shocks from direct contact with the steering mechanics, it will gradually deteriorate with prolonged use. Plastic ball sockets used at tie-rod ends can become loose after repeated attachment and removal. Periodic replacement of these parts will be required. In due course, replace any damaged components.
8. CHECKING DRIVE BELTDrive belt tension has to be checked periodically. Drive belt can be easily adjusted by changing pulley position. In addition, change it when damaged and clean it if it becomes dirty.
BODY REPAIRS
Even a slightly damaged or cracked body shell will worsen beyond repair due to running vibrations. Styrene bodies can be repaired using plastic cement or instant glues (Cyanoacrylates). Apply sheet styrene from the inside for reinforcement. Polycarbonate (Lexan) body shells cannot be repaired with cements, so use cloth tape or fiberglass reinforced tape for repairs. Polycarbonate sheet, cut from a body shell can be used as reinforcement under the cloth tape.
LONG TERM STORAGE
Remove all batteries from model. If the car is to be stored for an extended period, remove the wheels, or put the model on a stand with the wheels clear of the ground. This prevents the tires from deforming.
Copyright from TAMIYA RADIO CONTROL GUIDE BOOK 2005
2012年3月4日 星期日
HOBBYWING EZRun 150A ESC review
I had about an hour today to work on my RCs and pulled out the MM + KD36-74-6XL 2800kV and put in the Hobbywing EZRun 150A ESC and SL3674 2350kV motor.
The motor is the same physical size as the 6XL it replaces. It's a purdy blue instead of the KD36's red (I like blue much better). The motor includes a heatsink and a fan that's mounted onto the heatsink. The fan plugs into a fan output connector on the ESC. This is a great feature! It's so clean looking! See my EZRun 80A review for what the setup looks like. The EZRun 2350kV motor has about 1.5mm less inner winding clearance for screws than the KD36-6XL, so I had to use a spacer.
The 150A ESC is the same physical size as the 80A. However, it uses a different PCB (black instead of the 80A's green PCB) and much larger, higher voltage, higher capacitance input filter caps. It also uses 10ga wiring instead of 12ga found on the 80A. I wanted to keep some flexibility in the individual pieces, i.e. should I ever run a super hot motor or convert a 1/8 MT that weighs 12+lbs, I want to use the 10ga wire and 5.5mm bullet connectors, and if I decide to use the motor with an 80A other other ESC, I want to use the more common 4mm bullet connectors. So I soldered 5.5mm bullets to the ESC, 4mm bullets to the motor, and made 5.5mm bullet to 4mm bullet adapters. Works out quite nicely. A note to users of the 80A and 150A ESCs, do NOT use the "auto-detect" feature for LVC. It works with 2s, 4s, and 6s only. Even then, I recommend (as does the Hobbywing manual) to set the cell count yourself! I did auto-detect without fully reading the manual and didn't see that it didn't work with 3s, and it was slow and eventually kicked off LVC constantly. Once I manually set it to 3s, DAYAMN!!!...it started hauling ass! Tires ballooning! No steering because the front tires kept going off the ground! On 4s, acceleration would be even quicker! I do plan to also run it on 4s also. I have enough pinions to run both battery setups and I'd gear them to run about the same top speed. Which one I run at the track will depend on how the track is. If I need faster acceleration, I'll run the 4s. If I need more control, I might run the 3s. For general running around, I plan to run the 3s setup. It looks to be hitting 40+mph easily...possibly more. It was 8pm when I got it all working, so it was hard for me to see and I didn't want to floor the throttle at night where I can't see what I'll run into.
Added:
Ran the truggy a bit today. ST-1 looks about 39mph. The ST-1 accelerates really quickly and hits top speed very quickly. It looks overgeared (too short a gearing) with the 19T pinion and 50T spur. I'm wondering how it would do with a 46T Kyosho spur and 20T pinion.
I was doing top speed runs up and down the street till the batteries hit LVC. The hottest the 150A ESC got was 86F and the hottest the motor got was 112F and that was with a lot of braking because I was running out of space on the street. It was fairly cool today...about 67-73F depending on if the clouds came in or not.
The setup looks to have power to spare and seems to want taller gearing, which means even more top speed which would make me run out of street even faster!
A couple of reasons I like the EZRun much better than the MM it replaced:
1. NO GLITCHING AT ALL!!!! The MM setup would glitch a lot, which sucks when you're in mid-air and need to correct for your landing and it glitches and you land retarded! It's probably due to the combo with the external UBEC, but I didn't have a problem with the same type UBEC on another setup, so it was only with the MM.
2. It's FASTER!
Other reasons...
3. It runs so much cooler!
4. Built in UBEC is a much appreciated feature.
5. I love that little program card! So easy to pull it out and set everything up. I don't need to drag my laptop to my garage, hook up a USB cable, blah blah.
Compared to the 80A/SL3665 2300kV setup in my E-Sav, the E-Sav one is faster, but that's because it's running on 4s. I'm sure the 150A/SL3674 2350kV setup would be just as fast, if not faster and more brutal on 4s.
Here's a description of my truggy and setup:
Thunder Tiger ST-1 Truggy
EZRun 150A ESC
EZRun SL3674 2350kV Motor
Robinson Racing 19T Pinion
Stock TTR ST-1 aluminum shocks and black springs (springs preloaded 10mm front, 20mm rear)
AE 60wt shock oil
JConcepts Rulux 1/2-offset Wheels
HPI DirtBonz Tires
Currently 3s LiPos (2x 3s packs rated at 2750mAh each, 69A discharge in parallel = 5500mAh, 138A discharge)
If I run 4s, I will use a 12T or 13T pinion
The motor is the same physical size as the 6XL it replaces. It's a purdy blue instead of the KD36's red (I like blue much better). The motor includes a heatsink and a fan that's mounted onto the heatsink. The fan plugs into a fan output connector on the ESC. This is a great feature! It's so clean looking! See my EZRun 80A review for what the setup looks like. The EZRun 2350kV motor has about 1.5mm less inner winding clearance for screws than the KD36-6XL, so I had to use a spacer.
The 150A ESC is the same physical size as the 80A. However, it uses a different PCB (black instead of the 80A's green PCB) and much larger, higher voltage, higher capacitance input filter caps. It also uses 10ga wiring instead of 12ga found on the 80A. I wanted to keep some flexibility in the individual pieces, i.e. should I ever run a super hot motor or convert a 1/8 MT that weighs 12+lbs, I want to use the 10ga wire and 5.5mm bullet connectors, and if I decide to use the motor with an 80A other other ESC, I want to use the more common 4mm bullet connectors. So I soldered 5.5mm bullets to the ESC, 4mm bullets to the motor, and made 5.5mm bullet to 4mm bullet adapters. Works out quite nicely. A note to users of the 80A and 150A ESCs, do NOT use the "auto-detect" feature for LVC. It works with 2s, 4s, and 6s only. Even then, I recommend (as does the Hobbywing manual) to set the cell count yourself! I did auto-detect without fully reading the manual and didn't see that it didn't work with 3s, and it was slow and eventually kicked off LVC constantly. Once I manually set it to 3s, DAYAMN!!!...it started hauling ass! Tires ballooning! No steering because the front tires kept going off the ground! On 4s, acceleration would be even quicker! I do plan to also run it on 4s also. I have enough pinions to run both battery setups and I'd gear them to run about the same top speed. Which one I run at the track will depend on how the track is. If I need faster acceleration, I'll run the 4s. If I need more control, I might run the 3s. For general running around, I plan to run the 3s setup. It looks to be hitting 40+mph easily...possibly more. It was 8pm when I got it all working, so it was hard for me to see and I didn't want to floor the throttle at night where I can't see what I'll run into.
Added:
Ran the truggy a bit today. ST-1 looks about 39mph. The ST-1 accelerates really quickly and hits top speed very quickly. It looks overgeared (too short a gearing) with the 19T pinion and 50T spur. I'm wondering how it would do with a 46T Kyosho spur and 20T pinion.
I was doing top speed runs up and down the street till the batteries hit LVC. The hottest the 150A ESC got was 86F and the hottest the motor got was 112F and that was with a lot of braking because I was running out of space on the street. It was fairly cool today...about 67-73F depending on if the clouds came in or not.
The setup looks to have power to spare and seems to want taller gearing, which means even more top speed which would make me run out of street even faster!
A couple of reasons I like the EZRun much better than the MM it replaced:
1. NO GLITCHING AT ALL!!!! The MM setup would glitch a lot, which sucks when you're in mid-air and need to correct for your landing and it glitches and you land retarded! It's probably due to the combo with the external UBEC, but I didn't have a problem with the same type UBEC on another setup, so it was only with the MM.
2. It's FASTER!
Other reasons...
3. It runs so much cooler!
4. Built in UBEC is a much appreciated feature.
5. I love that little program card! So easy to pull it out and set everything up. I don't need to drag my laptop to my garage, hook up a USB cable, blah blah.
Compared to the 80A/SL3665 2300kV setup in my E-Sav, the E-Sav one is faster, but that's because it's running on 4s. I'm sure the 150A/SL3674 2350kV setup would be just as fast, if not faster and more brutal on 4s.
Here's a description of my truggy and setup:
Thunder Tiger ST-1 Truggy
EZRun 150A ESC
EZRun SL3674 2350kV Motor
Robinson Racing 19T Pinion
Stock TTR ST-1 aluminum shocks and black springs (springs preloaded 10mm front, 20mm rear)
AE 60wt shock oil
JConcepts Rulux 1/2-offset Wheels
HPI DirtBonz Tires
Currently 3s LiPos (2x 3s packs rated at 2750mAh each, 69A discharge in parallel = 5500mAh, 138A discharge)
If I run 4s, I will use a 12T or 13T pinion
HobbyWing EZRun 80A Review
Part 1: Initial Observations
I picked up one of Mike's HobbyWing EZRun 80 ESCs he now has in his store and thought I'd provide my humble opinions on it.
Some spec highlights: 80A continuous/270A burst, 4s/12 NiMH cells voltage, 3A switching BEC, 0.0018 on resistance. We'll see about the probability of those specs later.
First, a pic of the box contents. Comes with the ESC with dual Deans-compatible connectors pre-soldered on the power wires (seems like it is meant for dual battery applications) and 4mm bullets on the motor wires. Wires are 12GA. There's extra heatshrink, a few zip-ties, and a couple 3mm screws for mounting. The throttle cable is wrapped around a ferrite ring near the servo connector for reduced RF interference. The ESC has two mounting tabs built into the plastic case.
A couple of pictures showing relative size compared to a MMM. Yeah, it's that big.
The next picture shows the side where the fan and throttle cables are located. The switch is in a little box along with the program button connected via a servo wire. The throttle and switch wires are glued in place to act as a strain relief to protect the traces. The fan connector/wire has an extra output for a motor fan if desired (optional item). This ESC probably isn't meant to be waterproof, but HobbyWing did a pretty good job in sealing the ESC because there is a rubber seal all the way around where the heatsink meets the PCB, and where the bottom case meets the PCB. And any exposed PCB has a conformal coating.
Now for the guts! The fan is held on via four 5mm hex head (3mm) screws. The PCB is sandwiched between the heatsink and bottom case. The switching BEC is located on the brains board inside a little metal case, presumably to shield nearby components from switching noise.
I was pretty anxious to see the FETs, so I was disappointed when I removed the heatsink and found none there! This side of the PCB has heatspreader bars which touch the heatsink via a thermal pad. I kinda like this setup because it helps protect the fairly delicate FET component cases from accidental damage from jarring the heatsink.
And a view of the actual FETs sandwiched between the main and brain boards, which are soldered together via jumper pin headers.
Now for the fun part. Due to the way the PCBs were arranged, I had a heck of a time getting the FET part number, but with the use of creative lighting and a makeshift jewelers monacle, I was able to make out one of the FET part numbers as IRF3709Z. And there are 18 of these on this ESC.
Looking at the datasheet, we see that each of these FETs are rated for 30V, ~0.006 ohms (depends on gate drive), and 62A @ 100*C (212*F). Since there are 6 FETs on at any one time, 3 of which controlling each motor phase, that brings the current rating to 186A continuous and an on-resistance of around 0.002 ohms. Hmm, not bad at all. Seems like HobbyWing rated this ESC pretty realistically taking into account the temperatures we run these at. And the 270A burst rating seems possible judging from what the datasheet says based on the duration and duty cycle of the pulses. I really didn't want to calculate it out, but you are free to do so if you want.
The three input caps on the ESC are rated 470uF and 25v for a total capacitance of 1,410uF. The 4s rating on this ESC seems pretty conservative. Even running 5s lipo fresh off the charger, the caps would still run 16% below their voltage rating, and the FETs would be running 30% below their rating. But, even if the components might support 5s, I don't know if the firmware will let it arm at 5s, so it's just speculation right now. I'm not saying everyone should run 5s on this ESC, but we all know people will push them beyond the ratings - you know who you are! However, I would NOT run 6s on this at all. That would be pushing the caps too far and the FETs would have hardly any headroom for any back-EMF spikes.
In reading the hobbywing manual, I was pleased to see a well-rounded set of programming features: adjustable lipo cutoff, manual lipo cell programming (it will do auto-cell detect, but only for certain pack arrangements), etc. One really neat feature that stood out is the motor reversal. This can be done in three ways; 1) swap any two wires, 2) via ESC programming, and 3) simply by activating the transmitter servo reversing function (have to recalibrate the transmitter after this one though). This ESC does work with an optional programming card if counting motor beeps is too taxing for you.
All in all, this looks and specs out to be a VERY solid ESC with realistic/conservative ratings. Construction is top-notch too. Unfortunately, I do not have a vehicle I can test this in at the moment, but I will soon. I wanted to get Part 1 of the review out first.
EDIT A couple more tests with my bench power supply at 14.76v DC:
- ESC current draw with switch "off": 0mA. Hmm, it seems that this ESC won't drain your batteries if you accidentally leave them plugged in as long as you shut off the switch, but I wouldn't want to find out the hard way.
- ESC current draw with no motor, no load on the BEC, and the fan disconnected: 21mA (373mW)
- ESC current draw with no motor, no load on the BEC, but with the fan connected: 177mA (2.61w)
- ESC current draw with no motor, 2.5 ohm load on the BEC, and the fan disconnected: 999mA (14.75w)
I also tested the BEC a little.
- With no load (fan disconnected), BEC voltage was 5.84v with 23mV of 1163Hz AC ripple.
- With a 2.5 ohm load, BEC voltage was 5.58v with 18mV of 394Hz AC ripple. This equates to 2.23A and 12.44w. Efficiency at this load was 84%.
Efficiency is on par with typical switching regulators. I found it interesting that noise decreased with load. Odd BEC switching frequency though. I expected frequencies around 15kHz.
*************************************************
Part 2: Operation
I got a new motor mount and battery tray from Mike yesterday, and so was able to do a little running and offer my humble opinion on the performance of this ESC.
I hooked it up in my Hyper8 buggy: Neu 1512/2d (kv=2650) on 4s lipo (5Ah), geared 46/12. Top speed calculates to around 40mph.
First thing I tried was slow speed running. If you just lightly apply the throttle, the motor "chatters" similar to the MM/MMM at less than 1mph. When you give it a tad more, it stops chattering and starts to move, but does this surge/slow/surge/slow behavior. Here is a small (and I mean small) video of what I am talking about: Video.
I spoke with someone running a 7XL and it does the same thing, so it's nothing to do with the motor being slotted or 4 pole. So, it's not really good for slow running. Anything above ~3-4mph works fine though. Plenty of power when you goose it.
When I started out, I ran with the fan removed and the body on. Within 10 minutes of running at normal (fast) speed, the ESC thermaled. I re-installed the fan and once I let it cool, I was able to run the rest of the time without any more thermaling. Temps after the run was ~115*F (55*F ambient) with the fan. So, the fan IS absolutely required.
IMO, this ESC is too small to use on for 1/8 scale applications, but I think it would work great on a lighter 1/10 scale vehicle, geared right, and might even be able to get away with running without the fan. For 1/8 scale use, the EZRun150 would probably be a better bet for cooler running.
I picked up one of Mike's HobbyWing EZRun 80 ESCs he now has in his store and thought I'd provide my humble opinions on it.
Some spec highlights: 80A continuous/270A burst, 4s/12 NiMH cells voltage, 3A switching BEC, 0.0018 on resistance. We'll see about the probability of those specs later.
First, a pic of the box contents. Comes with the ESC with dual Deans-compatible connectors pre-soldered on the power wires (seems like it is meant for dual battery applications) and 4mm bullets on the motor wires. Wires are 12GA. There's extra heatshrink, a few zip-ties, and a couple 3mm screws for mounting. The throttle cable is wrapped around a ferrite ring near the servo connector for reduced RF interference. The ESC has two mounting tabs built into the plastic case.
A couple of pictures showing relative size compared to a MMM. Yeah, it's that big.
The next picture shows the side where the fan and throttle cables are located. The switch is in a little box along with the program button connected via a servo wire. The throttle and switch wires are glued in place to act as a strain relief to protect the traces. The fan connector/wire has an extra output for a motor fan if desired (optional item). This ESC probably isn't meant to be waterproof, but HobbyWing did a pretty good job in sealing the ESC because there is a rubber seal all the way around where the heatsink meets the PCB, and where the bottom case meets the PCB. And any exposed PCB has a conformal coating.
Now for the guts! The fan is held on via four 5mm hex head (3mm) screws. The PCB is sandwiched between the heatsink and bottom case. The switching BEC is located on the brains board inside a little metal case, presumably to shield nearby components from switching noise.
I was pretty anxious to see the FETs, so I was disappointed when I removed the heatsink and found none there! This side of the PCB has heatspreader bars which touch the heatsink via a thermal pad. I kinda like this setup because it helps protect the fairly delicate FET component cases from accidental damage from jarring the heatsink.
And a view of the actual FETs sandwiched between the main and brain boards, which are soldered together via jumper pin headers.
Now for the fun part. Due to the way the PCBs were arranged, I had a heck of a time getting the FET part number, but with the use of creative lighting and a makeshift jewelers monacle, I was able to make out one of the FET part numbers as IRF3709Z. And there are 18 of these on this ESC.
Looking at the datasheet, we see that each of these FETs are rated for 30V, ~0.006 ohms (depends on gate drive), and 62A @ 100*C (212*F). Since there are 6 FETs on at any one time, 3 of which controlling each motor phase, that brings the current rating to 186A continuous and an on-resistance of around 0.002 ohms. Hmm, not bad at all. Seems like HobbyWing rated this ESC pretty realistically taking into account the temperatures we run these at. And the 270A burst rating seems possible judging from what the datasheet says based on the duration and duty cycle of the pulses. I really didn't want to calculate it out, but you are free to do so if you want.
The three input caps on the ESC are rated 470uF and 25v for a total capacitance of 1,410uF. The 4s rating on this ESC seems pretty conservative. Even running 5s lipo fresh off the charger, the caps would still run 16% below their voltage rating, and the FETs would be running 30% below their rating. But, even if the components might support 5s, I don't know if the firmware will let it arm at 5s, so it's just speculation right now. I'm not saying everyone should run 5s on this ESC, but we all know people will push them beyond the ratings - you know who you are! However, I would NOT run 6s on this at all. That would be pushing the caps too far and the FETs would have hardly any headroom for any back-EMF spikes.
In reading the hobbywing manual, I was pleased to see a well-rounded set of programming features: adjustable lipo cutoff, manual lipo cell programming (it will do auto-cell detect, but only for certain pack arrangements), etc. One really neat feature that stood out is the motor reversal. This can be done in three ways; 1) swap any two wires, 2) via ESC programming, and 3) simply by activating the transmitter servo reversing function (have to recalibrate the transmitter after this one though). This ESC does work with an optional programming card if counting motor beeps is too taxing for you.
All in all, this looks and specs out to be a VERY solid ESC with realistic/conservative ratings. Construction is top-notch too. Unfortunately, I do not have a vehicle I can test this in at the moment, but I will soon. I wanted to get Part 1 of the review out first.
EDIT A couple more tests with my bench power supply at 14.76v DC:
- ESC current draw with switch "off": 0mA. Hmm, it seems that this ESC won't drain your batteries if you accidentally leave them plugged in as long as you shut off the switch, but I wouldn't want to find out the hard way.
- ESC current draw with no motor, no load on the BEC, and the fan disconnected: 21mA (373mW)
- ESC current draw with no motor, no load on the BEC, but with the fan connected: 177mA (2.61w)
- ESC current draw with no motor, 2.5 ohm load on the BEC, and the fan disconnected: 999mA (14.75w)
I also tested the BEC a little.
- With no load (fan disconnected), BEC voltage was 5.84v with 23mV of 1163Hz AC ripple.
- With a 2.5 ohm load, BEC voltage was 5.58v with 18mV of 394Hz AC ripple. This equates to 2.23A and 12.44w. Efficiency at this load was 84%.
Efficiency is on par with typical switching regulators. I found it interesting that noise decreased with load. Odd BEC switching frequency though. I expected frequencies around 15kHz.
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Part 2: Operation
I got a new motor mount and battery tray from Mike yesterday, and so was able to do a little running and offer my humble opinion on the performance of this ESC.
I hooked it up in my Hyper8 buggy: Neu 1512/2d (kv=2650) on 4s lipo (5Ah), geared 46/12. Top speed calculates to around 40mph.
First thing I tried was slow speed running. If you just lightly apply the throttle, the motor "chatters" similar to the MM/MMM at less than 1mph. When you give it a tad more, it stops chattering and starts to move, but does this surge/slow/surge/slow behavior. Here is a small (and I mean small) video of what I am talking about: Video.
I spoke with someone running a 7XL and it does the same thing, so it's nothing to do with the motor being slotted or 4 pole. So, it's not really good for slow running. Anything above ~3-4mph works fine though. Plenty of power when you goose it.
When I started out, I ran with the fan removed and the body on. Within 10 minutes of running at normal (fast) speed, the ESC thermaled. I re-installed the fan and once I let it cool, I was able to run the rest of the time without any more thermaling. Temps after the run was ~115*F (55*F ambient) with the fan. So, the fan IS absolutely required.
IMO, this ESC is too small to use on for 1/8 scale applications, but I think it would work great on a lighter 1/10 scale vehicle, geared right, and might even be able to get away with running without the fan. For 1/8 scale use, the EZRun150 would probably be a better bet for cooler running.
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