Checking amp draw on a motor
09-01-2009 | 07:09 PM
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From: honolulu,
HI
Checking amp draw on a motor
I wanted to check what the amp draw on my stock motor was and according to my memmory (which may be fuzzy at best), I could just hook a multimeter (with a big enough fuse to handle the amp draw; yes Iknow not to put a penny in to the fuse slot... Iknow Ineed a good enough multimeter to handle the high amps and not just replace the fuse with a higher rated one), put it in amp mode and place this between the motor and battery (in series) and then turn the throttle to high. Is this correct or am Inot remembering things correctly from my time in highschool?
thanks
thanks
09-01-2009 | 07:37 PM
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From: Grant,
FL
RE: Checking amp draw on a motor
That's the easiest way, but difficult to do for high current draws as you will have difficulty finding a meter with the ability to directly handle high curents. My multimeter only handles 10 amps.
09-01-2009 | 07:55 PM
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From: honolulu,
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RE: Checking amp draw on a motor
I use to have a load tester for car batteries but i think that one is too high for this application and may not show anything at all...
ORIGINAL: SushiSeeker
That's the easiest way, but difficult to do for high current draws as you will have difficulty finding a meter with the ability to directly handle high curents. My multimeter only handles 10 amps.
That's the easiest way, but difficult to do for high current draws as you will have difficulty finding a meter with the ability to directly handle high curents. My multimeter only handles 10 amps.
09-01-2009 | 08:01 PM
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From: Houston, TX
RE: Checking amp draw on a motor
ORIGINAL: eccvets
I wanted to check what the amp draw on my stock motor was and according to my memmory (which may be fuzzy at best), I could just hook a multimeter (with a big enough fuse to handle the amp draw; yes I know not to put a penny in to the fuse slot... I know I need a good enough multimeter to handle the high amps and not just replace the fuse with a higher rated one), put it in amp mode and place this between the motor and battery (in series) and then turn the throttle to high. Is this correct or am I not remembering things correctly from my time in highschool?
thanks
I wanted to check what the amp draw on my stock motor was and according to my memmory (which may be fuzzy at best), I could just hook a multimeter (with a big enough fuse to handle the amp draw; yes I know not to put a penny in to the fuse slot... I know I need a good enough multimeter to handle the high amps and not just replace the fuse with a higher rated one), put it in amp mode and place this between the motor and battery (in series) and then turn the throttle to high. Is this correct or am I not remembering things correctly from my time in highschool?
thanks
What do you mean by a stock motor? Are you talking cars?
09-01-2009 | 08:07 PM
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From: honolulu,
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RE: Checking amp draw on a motor
No, I was talking about rc plane stock eletrical motors. I was just wondering how many amps it drew with the stock prop which came with the plane as I was considering changing the prop to a diffferent size.
ORIGINAL: GaryHarris
What do you mean by a stock motor? Are you talking cars?
ORIGINAL: eccvets
I wanted to check what the amp draw on my stock motor was and according to my memmory (which may be fuzzy at best), I could just hook a multimeter (with a big enough fuse to handle the amp draw; yes Iknow not to put a penny in to the fuse slot... Iknow Ineed a good enough multimeter to handle the high amps and not just replace the fuse with a higher rated one), put it in amp mode and place this between the motor and battery (in series) and then turn the throttle to high. Is this correct or am Inot remembering things correctly from my time in highschool?
thanks
I wanted to check what the amp draw on my stock motor was and according to my memmory (which may be fuzzy at best), I could just hook a multimeter (with a big enough fuse to handle the amp draw; yes Iknow not to put a penny in to the fuse slot... Iknow Ineed a good enough multimeter to handle the high amps and not just replace the fuse with a higher rated one), put it in amp mode and place this between the motor and battery (in series) and then turn the throttle to high. Is this correct or am Inot remembering things correctly from my time in highschool?
thanks
What do you mean by a stock motor? Are you talking cars?
09-01-2009 | 08:16 PM
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From: Littleton, CO
RE: Checking amp draw on a motor
You really should consider getting a good watt meter. The watt meter goes between your battery and ESC, and will tell you voltage, amperage draw, watts, and milliamps used. It's much more suited for RC use than a standard DVOM.
I use an E-flite watt meter, very high capacity, and was just under $40.00
I use an E-flite watt meter, very high capacity, and was just under $40.00
09-01-2009 | 08:17 PM
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From: honolulu,
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RE: Checking amp draw on a motor
I was assuming thats what a watts meter was (the multimeter setup). Where can you buy specific watt meters from? which are some good brands? is one better then another? Is this the one you got http://www.amazon.com/dp/B000BLAL8Y/...SIN=B000BLAL8Y
ORIGINAL: speedy72vega
You really should consider getting a good watt meter. The watt meter goes between your battery and ESC, and will tell you voltage, amperage draw, watts, and milliamps used. It's much more suited for RC use than a standard DVOM.
I use an E-flite watt meter, very high capacity, and was just under $40.00
You really should consider getting a good watt meter. The watt meter goes between your battery and ESC, and will tell you voltage, amperage draw, watts, and milliamps used. It's much more suited for RC use than a standard DVOM.
I use an E-flite watt meter, very high capacity, and was just under $40.00
09-01-2009 | 08:54 PM
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From: Houston, TX
RE: Checking amp draw on a motor
I'm confused eccvets. You might get better info on the electric forum when it comes to planes. I know a little about amp draw and tuning motors for cars, and even used a Turbo 30 to check amp draw on a glider back in the day with a 540 motor and a 1400 mAh 6 cell pack. The bigger the prop, the higher the amp draw in it's simplist form.
Need more info.
Need more info.
09-02-2009 | 02:56 AM
#10
RE: Checking amp draw on a motor
The best way to measure motor draw is to use a wattmeter or similar product, the one I use is a Turnigy and works will, measures volts, amps, mah used and shows watts draw. Only way to setup an electric model.
Cheers
Cheers
09-02-2009 | 08:03 AM
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From: Littleton, CO
RE: Checking amp draw on a motor
ORIGINAL: eccvets
I was assuming thats what a watts meter was (the multimeter setup). Where can you buy specific watt meters from? which are some good brands? is one better then another? Is this the one you got http://www.amazon.com/dp/B000BLAL8Y/...SIN=B000BLAL8Y
I was assuming thats what a watts meter was (the multimeter setup). Where can you buy specific watt meters from? which are some good brands? is one better then another? Is this the one you got http://www.amazon.com/dp/B000BLAL8Y/...SIN=B000BLAL8Y
ORIGINAL: speedy72vega
You really should consider getting a good watt meter. The watt meter goes between your battery and ESC, and will tell you voltage, amperage draw, watts, and milliamps used. It's much more suited for RC use than a standard DVOM.
I use an E-flite watt meter, very high capacity, and was just under $40.00
You really should consider getting a good watt meter. The watt meter goes between your battery and ESC, and will tell you voltage, amperage draw, watts, and milliamps used. It's much more suited for RC use than a standard DVOM.
I use an E-flite watt meter, very high capacity, and was just under $40.00
These meters are specifically designed for RC use, and an essential tool IMHO. It will save you many dollars in burnt motors and ESC's.
09-02-2009 | 11:44 AM
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From: Poolesville, MD
RE: Checking amp draw on a motor
ORIGINAL: speedy72vega
These meters are specifically designed for RC use, and an essential tool IMHO. It will save you many dollars in burnt motors and ESC's.
These meters are specifically designed for RC use, and an essential tool IMHO. It will save you many dollars in burnt motors and ESC's.
No truer words!
I was a bit remiss to spend the money on a good Watt meter at first.
Now I consider my reluctance somewhat stupid.
09-02-2009 | 11:51 AM
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From: St Paul,
OR
RE: Checking amp draw on a motor
http://www.rcgroups.com/forums/showt...LAR+WATT+METER
Here is the link to the $3 watt meter. It is very easy to make and very accurate. It will also tell you the exact same information as the high dollar watt meters, so there is no real need to spend $40+ when you can make your own for much cheaper.
Here is the link to the $3 watt meter. It is very easy to make and very accurate. It will also tell you the exact same information as the high dollar watt meters, so there is no real need to spend $40+ when you can make your own for much cheaper.
09-02-2009 | 02:01 PM
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From: honolulu,
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RE: Checking amp draw on a motor
That seems pretty simple if all you need to do is to solder a 1K resistor to the volts pin. Thanks for the link, i tried looking for it but I couldnt find that post.
ORIGINAL: Allfat
http://www.rcgroups.com/forums/showt...LAR+WATT+METER
Here is the link to the $3 watt meter. It is very easy to make and very accurate. It will also tell you the exact same information as the high dollar watt meters, so there is no real need to spend $40+ when you can make your own for much cheaper.
http://www.rcgroups.com/forums/showt...LAR+WATT+METER
Here is the link to the $3 watt meter. It is very easy to make and very accurate. It will also tell you the exact same information as the high dollar watt meters, so there is no real need to spend $40+ when you can make your own for much cheaper.
