Where to find 6 and 12 watt resistors?

[mulligan]

Judging by the charts have for my motors (Kelling 23H276-30-8B and 23H286-20-8b) I will need .7 Ohm - 6 watt and 3 ohm - 12 Watt resistors.

Where can I find these online? Locally I have zero options other then The Source and they only carry up to .5 watt resistors.

Thanks,
shawn

[Al_The_Man]

DigiKey have excellent service to Canada, next day air and no customs.
Or In Canada ElectroSonic or across Canada local store if you have is Active Electronics.
Al.

[johnmac]

What controller are you using? If you don't have one yet, you might consider using a controller with built-in current limiting.

John

[mulligan]

3 Ohm - 12 Watt - http://www.digikey.com/scripts/DkSea...=FVTS10-3.0-ND

.7 Ohm - 10 Watt - http://www.digikey.com/scripts/DkSea...name=20JR75-ND

Thanks Al!

Are these what I am looking for?

[mulligan]

Originally Posted by johnmac What controller are you using? If you don't have one yet, you might consider using a controller with built-in current limiting. John

Right now I am attempting to get my moor running. I am using a power supply with 8v, 5v and 12v pins, a break out board from hubbardcnc and K179 Stepper drivers from hubbard also.
As far as I know resistors are my onmly option to limit voltage with what I have?

[jeffs555]

It would help to know what drives and power supply you are using, and what you are trying to accomplish. Those resistor values just don't sound right. On a non-chopper drive, those resistor values would only be good for a very low voltage supply. Also, to allow a safety factor, you generally want the wattage rating of the resistors to be at least twice the calculated value.

[jeffs555]

Ok, that explains it. I assume you are using the 3 ohm to run the KL23H286-20-8B off a 12 volt supply and the .7ohm to run the 23H276-30-8B off a 5 volt supply. In that case you would want to at least double your wattage ratings to allow a safety factor.

[mulligan]

Originally Posted by jeffs555 Ok, that explains it. I assume you are using the 3 ohm to run the KL23H286-20-8B off a 12 volt supply and the .7ohm to run the 23H276-30-8B off a 5 volt supply. In that case you would want to at least double your wattage ratings to allow a safety factor.

Ok I will try to find higher watage resisors. Thanks for the help.

[vulcom1]

Go to Digikey's web site. You will find what you need on a search in the online catalouge. If you need to mount a large resistor I prefer the alum. housed ones as they have the heatsink. You should at least double your wattage as mentioned.
John