Determining amps on contactor
#1
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Determining amps on contactor
Hi,
I need to replace my contactor but I can't determine the amps for the replacement. The current contactor only shows me 240 VAC 50/60 Hz. It appears to be a single pole contactor.
Any ideas on how I figure this out?
Thanks,
Erik
I need to replace my contactor but I can't determine the amps for the replacement. The current contactor only shows me 240 VAC 50/60 Hz. It appears to be a single pole contactor.
Any ideas on how I figure this out?
Thanks,
Erik
#2
With the unit up and running and a clamp-on meter set to read amps, clamp the meter around the wire connected to that pole. The reading you get is the RLA (running load amps). This is what is called an "inductive load". Armed with that info go to the place where you're planning on buying the contactor, tell them is for an hvac application and give them the value you just read.
You may also take the M/N of this unit (that tells its size) and give the counter person the info. They'll know what to give you.
Lastly, if you post the info on the MFR and M/N, maybe we'll be able to do a web-search and help you out with part number and specifications.
You may also take the M/N of this unit (that tells its size) and give the counter person the info. They'll know what to give you.
Lastly, if you post the info on the MFR and M/N, maybe we'll be able to do a web-search and help you out with part number and specifications.
#6
M/N: AH048G2
This is a 4-ton condensing unit
compressor running amps: 23.7
Fan running amps: 1.4
A 1-or 2-pole, 24V-coil contactor, with contacts rated for an inductive load of 30A or more (running amps) and 130A or more (Locked rotor amps) will do.
This is a 4-ton condensing unit
compressor running amps: 23.7
Fan running amps: 1.4
A 1-or 2-pole, 24V-coil contactor, with contacts rated for an inductive load of 30A or more (running amps) and 130A or more (Locked rotor amps) will do.
#7
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I was going to get the part from Grainger but they seem a bit overpriced, so if you have any online resources that sell the part at a good price that would greatly appreciated.
Thanks for all of your help on this!
Thanks for all of your help on this!
#11
I'm surprised. Graingers usually have good prices. This part should go for about $15 (maybe a couple of dollars more or so)
At any rate, if you call someone to do the job, expect no less than $100 for them coming...so if Graingers is charging you 20-or-30 bucks for this, you're still saving.
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How expensive?
I'm surprised. Graingers usually have good prices. This part should go for about $15 (maybe a couple of dollars more or so)
At any rate, if you call someone to do the job, expect no less than $100 for them coming...so if Graingers is charging you 20-or-30 bucks for this, you're still saving.
I'm surprised. Graingers usually have good prices. This part should go for about $15 (maybe a couple of dollars more or so)
At any rate, if you call someone to do the job, expect no less than $100 for them coming...so if Graingers is charging you 20-or-30 bucks for this, you're still saving.
#13
You need to replace the single pole with a single pole if that is what you had. I did not dig for the hour it would take to find out but if your unit utilizes a compressor heater it may not function correctly unless you do some rewiring. For a novice it is best to get a identical part and wire it up identically, that might save a bunch of problems down the road.