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Centralized Emergency Lighting Inverter #129854 09/28/05 07:40 AM
Joined: Jul 2001
Posts: 311
Frank Cinker Offline OP
A 5000 watt, 120 volt centralized emergency lighting inverter provides power for one of our municipal recreation centers. When the test button is pushed the transfer relay operates but the inverter does not activate. The batteries are fine and the fuses have been checked. Is there a way to temporarily bypass all switching and simply test the inverter only?

[This message has been edited by Frank Cinker (edited 09-28-2005).]

[This message has been edited by Frank Cinker (edited 09-28-2005).]

[This message has been edited by Frank Cinker (edited 09-28-2005).]

[This message has been edited by Frank Cinker (edited 09-28-2005).]

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Re: Centralized Emergency Lighting Inverter #129855 09/28/05 07:46 PM
Joined: Oct 2000
Posts: 2,720
Scott35 Offline
Broom Pusher and

Sounds familiar, so here are some ideas to try.
BTW, I viewed the images, and it appears that the Batteries are in the cabinet to the left, and all the control + inverter stuff is in the right side cabinet


[*] Verify that there is 120VDC at the Battery with the output leads,

[*] Verify the polarity is correct at the Inverter Assembly's DC Input,

[*] Verify that the UPS System control is set for "Normal Use", not in any type of test mode or override mode,

[*] Verify that the Transformer(s) connections are setup correctly - input and output wise,

[*] Check that all interlocking relays are functioning when the transfer takes place,

[*] Verify that the main system power Transfer contactor(s) are latching / unlatching as needed, and that any interlock contacts are functioning + wires are terminated properly,

[*] Verify that the input and output AC Power Circuitry is terminated properly, and that there is an output - independent of the input power supply - during normal mode operation,

[*] Verify the H.O.A. switch is in the Auto setting.

Try turning off the Circuit Breaker that feeds the UPS Inverter, and see if this test makes the device work properly.
Also, test the output voltage during the tests you have described, and verify the output is AC, not DC; and that the output voltage is correct.

The inverter should be supplying output power, even when the system is in normal operation (unless this inverting supply is not a "UPS" type).

If all field terminations + Battery terminations & jumpers are correct, along with proper input voltages & configurations, then the problem exists within the control logic and / or other hardware / devices; which would be a Manufacturer's issue.

A call to them should be made, and the word "Warantee" should be mentioned [Linked Image]

If this is not a new UPS system, or there is no current warantee, then it's time to get specs and schematics for it and begin looking for which parts "lost their smoke"!!!

Good luck with this.
Let us know how things turn out.


[This message has been edited by Scott35 (edited 09-28-2005).]

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Re: Centralized Emergency Lighting Inverter #129856 10/04/05 11:56 AM
Joined: Jul 2001
Posts: 311
Frank Cinker Offline OP
Thank you for your input Scott. I should have mentioned it is an interruptible power supply. The battery bank output is 54 volts DC. The inverter output is 120 volts AC. As previously mentioned it is a 5000 watt centralized emergency lighting inverter. It is approx. 15 years old. Trouble-shooting this kind of unit is not a forte of mine I must admit. For the most part I used your trouble-shooting method. All seemed to check out okay. My "hunch" is that it is either the control circuit board or the inverter itself. What do you think? I know I didn't provide you with a great deal of information. I'm just curious what you think.

Control Circuit Board Photo:

Thank you,

[This message has been edited by Frank Cinker (edited 10-04-2005).]

Re: Centralized Emergency Lighting Inverter #129857 10/04/05 10:21 PM
Joined: Oct 2004
Posts: 803
mxslick Offline
Hi Frank:

If I may toss my oars into the water here, it looks like there are some overheated components on that control circuit board, so it would be my first suspect. It also appears to be older technology than 15 years, even though the system dates from 15 it could be a much older design.

Is the manufacturer still in business? Perhaps they can provide a schematic or troubleshooting tips, maybe even a repair/exchange on the control board. Armed with a good schematic you may be able to make voltage checks at various points to help isolate the problem.

I'm in So Cal and if you want to give as many details as you can you may email me direct.

Hope this helps!


edited for dyslexic spelling...

[This message has been edited by mxslick (edited 10-04-2005).]

Stupid should be painful.


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