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Equi=Core Hum & Other Issues

I’ve owned a Core Power Tech Equi=Core 1800 for 6 months. Recently the transformer has started to hum inside the chassis. It happens when components are on and also when sources are powered down. The transformer hum is intermittent. It ranges from multiple times per day to 3 or 4 days without any hum. I never had DC on my dedicated lines before, so I picked up a Klein Tools AC/DC tester... https://www.kleintools.com/catalog/electrical-testers/electronic-acdc-voltage-tester-12-240v-ac-15-2...
and when plugged into wall receptacles it indicated overload. Line voltage is steady at 122VAC and always has been.
What am I doing wrong, and how should I test for DC on the power line?

I discovered another problem when testing the Equi=Core duplex receptacles; they indicate inverted polarity. All house outlets measure correct polarity.
I’m looking for some assistance in diagnosing this hum. I’m not sure if it’s due to DC offset or if the torroid itself is vibrating in its mounting.

I know this is becoming a long thread, but I must mention that the Equi=Core now trips the breaker at the panel when powered on. It trips several times in a row, eventually allowing power-up. This is a 20A dedicated line from a subpanel which I’ve had for years.
Any advice is much appreciated.


lowrider57
lowrider57's avatar
lowrider57 OP
5,418 posts
 
Erik, what you’re saying makes sense for troubleshooting. But, since the hum issue is so random it may not present again for many hours or days.
I’m thinking that shutting off large appliances may be the way to go first, rather than sitting in the dark.

lowrider57's avatar
lowrider57 OP
5,418 posts
 
Tuffy, that’s interesting. As stated, I’ve had close to six months of flawless operation. I need to find what’s different now. I live in an old Philly rowhome so the cause could even be from a neighbor.

Plus I need to address the issue of tripping the circuit breaker.


uberwaltz's avatar
uberwaltz
13,381 posts
 
Jim
Is this the unit you bought from myself back in May last year?
Sorry to hear you are having issues with it.
Talk to Wally, he is a true gentleman IME.
Good luck sir!
lowrider57's avatar
lowrider57 OP
5,418 posts
 
Hi Uber. These problems came out of nowhere. Like the circuit breaker tripping, there’s no way the EquiCore is overloading a 20A circuit. That’s why I think the electrician should have a look first.

Of course I'll talk to Wally.

erik_squires
16,558 posts
 

I know this is becoming a long thread, but I must mention that the Equi=Core now trips the breaker at the panel when powered on.


Oh, I missed this entirely. Have your circuit checked. You didn’t just go through a lot of ice or rain did you? :)

But it IS possible something blew in the conditioner too. You may have a short there you didn't have before.
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