AC Compressor not Starting

Carrier appx. 4 ton, 10 years old.
Contactor pulls in, voltage ok on the load side, zero current. Didn't check at the moment of closing but w/in 10 seconds. No sound whatsoever of compressor-like noises.
Start windings @ 2.8 ohm, run winding @ 0.7 ohm, start-run @ 3.3 ohms.
Removed cap wires, discharged, DVM reads 3.5 M, reverse leads, open. Reverse again and open. Discharge cap and the process repeats.
No alarm annunciated on the control board.
Any thoughts?
Thanks.
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wrote:

the moment of closing but w/in 10 seconds. No sound whatsoever of compressor-like noises.

Do you have a capacitor checker?
Is it humming until the O/L trips out? If not you may just have a bad contactor
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carpboy wrote:

the moment of closing but w/in 10 seconds. No sound whatsoever of compressor-like noises.

Hi, Zero current? Then it indicates open circuit like open winding. No burnt smell, no spark from the contactor contacts?
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On 6/11/2012 12:10 PM, Stormin Mormon wrote:

In particular, did the OP measure line-to-line and get 240V.
Or measure line-to-ground and get 120V on each side. You can get this measurement with one side open (for instance a blown fuse).
--
bud--

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