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.


128x128lowrider57
@jea48 , I'll try and answer all your questions. Here goes...
I leave the EquiCore on 24 hrs/day. My weekly schedule changes so when there's two or three days I won't be listening, I shut it down. 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. Now I stand at the panel with the EQ power switch in the on position and retry the breaker every few seconds until resetting is successful. The 20A is a standard residential breaker.

The breaker on the EQ has never tripped and the unit has always run cool. All inputs are low-current-draw components; DAC, transport, iFi reclocker, LPS with 50VA torroid, Bluesound Node. (all digital, no SMPS) Amp and preamp are on a 2nd dedicated line.

 I will swap in my old Brick Wall conditioner when I have a chance. Good idea.


Post removed 
Either you fix the Equi=Core via 
_Underwally Or fix it your self   ?
I have 2 of the same in my Australian garage in the long hope I will have these fixed. The main issue ( Going back to 2018) why my Equi=Core came promIst to ship to Australia with AUS connectors when the opposite where delivered. US connectors where delivered, to me and my electronics companion were particularly disappointed. Now where to we get the US electronics required.
Australia is not close to seeking the required connector outlets and as such seek recuperative respective knowledge to be able to apply the respective corrections to make these EQUI=COREconnectors which were ordered however came with US outlets, which obviously we cannon use.
A readily and cheap solution would be appreciated.
AMG

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
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