Equi=Core Hum & Other Issues

lowrider57 OP3,544 posts  

02-26-2020  
 4:06pm


To power up the system, I turn on the Equi=Core, then the panel breaker trips immediately. I used to repeat this procedure but the panel tripped every time I turned the EQ on.

@lowrider57

That tells me the branch circuit wiring is fine. The 20 amp breaker didn’t trip until you turned on the EQ unit using the ON/OFF switch.

It sounds like you have been tripping and resetting the circuit breaker a whole bunch of times. Not just a few times. It sounds like it was the magnetic trip device in the breaker that was tripping the breaker open. I am not sure the magnetic trip device weakens with several repeated very high inrush current and or from a ground fault or short circuit event/s. I do know the overload thermal trip device does though. You weren’t tripping the breaker on overload, imo..... You said the breaker would trip immediately.


If the secondary of the transformer was not loaded, (say by at least 50% or more), from a cold start up the primary winding would not draw all that much inrush current. No where near enough current to trip a 20 amp breaker...
Just a stab in the dark I would say the transformer is the culprit. I would also guess what ever is going on it has been progressively getting worse. I would not try use it until you have it looked at.

As for the 20 amp breaker in the electrical electrical sub panel.
Because of all times the breaker has been tripped, and then you trying to close the breaker under a load. At a very high current load I might add. Possibly at a hundred amps or more, the contacts in the breaker have to be really burnt and pitted.
Jmho, I think you are darn lucky the contacts did not weld themselves together.


Side note:
I should mention depending on the breaker manufacture the 20 amp breaker may be a SWD rated breaker. An SWD rated breaker is rated to be used as a switch to turn on and off florescent lighting like you see in a store like Target and Walmart. (Now no doubt LED)... The calculated maximum continuous connected load for a 20 amp circuit breaker is 16 amps. 80% of 20 amps. You were switching a load of maybe 100 amps or more.....

Jim

@lowrider57

For some reason the above post, I originally posted last night, was corrupted after it looked fine after I posted it. The post this morning is the same without the corrupted part as seen at the top sentence of the post last night. I then deleted the post.

With that out of the way.....

I would like you to preform a test when you get a chance. Plug a vacuum cleaner into the wall outlet of the 20 amp dedicated circuit that has been tripping the breaker. Most walk behind vacuum cleaners have a so called 12 amp motor. That means if the motor is loaded, vacuuming carpet, it will draw 12 amps, or slightly less... That is a good load test for the branch circuit wiring as well as the branch circuit breaker.

It should power up fine without tripping the breaker. But,.... there is all them breaker trips and resets.... One thing for sure if the vacuum runs just fine that clears any finger pointing at the branch circuit wiring and breaker causing the problem.


You still need to hire an electrician and have him trouble shoot your situation. At the very least have the 20 amp breaker in the sub panel replaced.
I kept forgetting to ask, what manufacturer made the sub panel and breaker?
Example, Square D? Square D QO? Square D Homeline?

The electrician will be more than qualified to look at the Equi=Core unit. You can save some money by having the top cover already removed before he looks at it. You might ask him, when you call him, if he has a Megger? If he does ask him to bring it with him.

Megger is a trade name of an insulation tester. Example of:
https://www.grainger.com/product/MEGGER-Insulation-Tester-54JH70?ef_id=EAIaIQobChMI_Pu6tfHx5wIVx0XVC...

I would also let him know what manufacture made the sub panel. On the inside of the hinged cover it should list the manufacturer as well as the model number.
That way he will know for sure he has the 20 amp breaker in his Service Van when he comes to your home. Time is money....

Jim
.

 @jea48 
Square D QO main panel,
8 space 100 amp.

Going to try to have the electrician who did the install come to the house. Will call today.
 I was planning to open up the EquiCore before his service call....
-- Should I have the audio sources hooked up so he can test it under load?
-- What type of breaker should I request he bring; a heavy duty or commercial breaker?

Good idea to try the vacuum cleaner. As always, I appreciate your time.
Jim S.

@lowrider57

Square D QO. Good Choice.

No doubt he carries a Square D QO 120 breaker in his service van. Still wouldn’t hurt to tell him the breaker is a QO 120 breaker. Only a Square D QO breaker will work in the panel.

No need to have the audio equipment hooked up to the Equi Core unit. If he needs a load you can always use pretty much anything with a cord and plug you have in your home for a load.

You might prepare a place on the dining room table for him to look at the Equi Core unit So he doesn’t have to get down on his hands and knees. Make sure he has good lighting. Natural lighting works best.

Also you might mention the transformer has a 60/120V split phase secondary winding. The two outer 120V leads are both ungrounded that connect to the duplex receptacle AC Line, Mains, contacts.
The secondary winding center tap neutral lead is bonded, grounded, to the chassis and to the equipment ground contacts on the duplex receptacle outlets.
(NEC ARTICLE 647 Sensitive Electronic Equipment.)

Jim

@jea48  Thanks for the transformer wiring info.
I'd like to keep you updated if you don't mind. Electrician appt. is Tuesday; my service order states to inspect panel and subpanel, replace the subpanel breaker, and inspect/service the Equi=Core.

I pulled the EQ out of service and will pop the top this weekend. I have a Brick Wall passive conditioner in the circuit running digital devices, no issues.
But now I'm hearing hum from the power transformer in my Atma-sphere amp. It uses the second dedicated circuit from subpanel with my preamp. I'll have to check with Ralph, the amp is supposed to have a DC blocker built in. Preamp is Audio Note using their large EI transformer.

This leads me to the question; can DC offset be measured by the electrician either at the service panel or the wall receptacles?