Electric current clamp on meter

[Crosley.In.AZ]

ANy experience with the clamp on electric current measuring tool brands?

You clamp the tool head around a wire to measure the current flow.

I see tool brands and prices from 60 dollars to 260 dollars.

I am looking to measure the inline rush amp current on my a/c units on my house and shop.  My house unit specs out at 117 amps, the reading on the unit is 138 amps at start up.

The a/c service company was out 2 weeks ago.  Tell me I need a "hard start kit" on my 3.5 yr old unit to save stress on my compressor during start up. 249.00 dollars installed.  That is with a discount.

I found various hard start kits & you tube videos  on the internet.  A popular brand is around 45 to 50 dollars for my size a/c unit.  A brand :  5 2 1 Hard Start Kit , comes with relay and capacitor with 3 wires to hook up.

:!:

[Arnold]

Klein Tools at Home Depot have made me very happy Very expensive though. I have bought some of their electrical testers and hand tools. I would buy some of their stuff again  in a heartbeat. Price to me is their ONLY deterrent..one of those.."I really don't need or want to spend that much for this" I am pretty sure they will have the tester you want.

[Crosley.In.AZ]

Yes.  I have looked at the Klein brand tools.  Bought some.

I see Fluke , EUI , Klein as brands for the clamp on current tool. Some of the tools look like "copies or clones" of each other.

Guess I will close my eyes. Pick one from eBay or something.  

May be wiser to buy local , if the tools does not function properly ?

[wayne petty]

$14 at HF.

https://www.harborfreight.com/digital-clamp-meter-96308.html

if you are having hard start problems..  you will want to shut down the power to everything for a little while and go in and clean all the connections..

pull the circuit breakers out and clean the buss bars..  or at least pull the circuit breakers out and push them back in several times working thru the oxides that form on the buss bar and circuit breaker connections..

you will want to invest in several of the outlet testers.

https://www.harborfreight.com/catalogsearch/result/index/?dir=asc&order=EAScore%2Cf%2CEAFeatured+Weight%2Cf%2CSale+Rank%2Cf&q=outlet+tester

plug them in and cycle the HVAC on and off while somebody watches them.

OPEN COMMONS can cause hard starts and actually significant damage. to other electrical devices.

when the common is iffy..  and the resistance of the iffy connection is exceeded..  you start getting 240 volts across the L1 and L2 120 volt circuits..  stuff starts to explode..

loose or oxidized connections on L1 and L2 can have the same effect..


so you will want to have any electric clothes dryer cycled on and off while watching the outlet testers in close outlets.  but you will need an outlet tester that is plugged into the L1 side of the circuits and also into the L2 side.


i had to replace my microwave and several computers a while back.. the common was loose on the pole.. took the power company to find it.  darn lights in the kitchen would dim when the microwave was turned on.  

a friend out in hemet lost his AC condenser motor.. i told him to check for a loose common.. the ac guy came out and replaced it. said commons are not an issue..  the compressor failed the tech said. .  came back.. oops.. bad common.. power company found the loose common.. fixed it.. friend went to turn on the AC..  no cooling.. the tech had removed all the freon leaving a tiny hole in the tubing ..

[GPster]

AC starting may somewhat depend on the brand. Lennox supposedly make their own compressors and their system designs with their compressors doesn't require "Hard Start"'. The start winding on these compressors is fed off what we used (long time ago) to refer to as the "Run" capacitor because their compressors kind of "spin-up" rather than start hard. This type of compressor starting was used on "window ACs" and it worked well enough with smaller hp compressors but the capacitor was the most common problem for no start. Lennox uses their "run" capacitors with two mfd outputs so it serves double duty as a "run" capacitor for the condenser fan motor. If the compressor in your unit is wired this way I would check/replace this capacitor first, If it doesn't have a "Hard Start" relay and "start capacitor" on it I wouldn't think it wise to add one. If it has this type of components on it I would first replace these parts. Or check Wayne's ideas. If the voltage drops because of bad connection or neutral the amperage is going to rise.  If a "soft start" compressor won't start but the wiring is OK it might be because the refrigerant pressures haven't equalized because it is trying to restart too soon or maybe it's overcharged. I remember sometimes when a compressor wouldn't restart and kicked off on the compressor's overload the system might react to it's overload resetting by clicking off again. Put these ideas with the others. GPster

[Rrumbler]

For reasonably good - read: suitable for industry use - Klein, Greenlee, Amprobe are good and reliable, without breaking your wallet. a Fluke is great, but hella expensive.  There are many other Asian knockoffs that will work, too, but I would question their accuracy.  I have a Klein, and an Amprobe, plus a plug in clamp that works with one of my analog meters.