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OTCU 150C Not Transferring from Street Power


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  #1  
Old 01-05-2018, 01:22:19 PM
hoghunter69 hoghunter69 is offline
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Default OTCU 150C Not Transferring from Street Power

A couple months ago I started a thread after the governor belt on my 35EK broke and sent the engine into weed eater mode. Luckily someone was home and powered off the engine. Repairs were made, engine checked out and power was being generated. In the meantime I had disabled the exerciser clock and just ran the generator a few times while I was cutting grass to help drown out the noise. According to the annunciator panel on the OTC 150 it was ready to take a transfer.

Today I was working from home in 15 degree weather and decided to exercise the generator via the transfer switch. Turned the key, generator started, panel showed ready to transfer and no transfer occurred. Checked the switches that showed exercise with CLOCK and LOCAL TEST were both set to load. Motor Disconnect in AUTO. I've done this numerous times prior to the over-rev condition without issue.

Attached are pictures 10 minutes after the generator cranked. Hard to see with the flash but neither Source 1 (utility) or Source 2 (generator) are showing available. After the generator powered down, SOURCE 1 showed available and RETRANSFER complete.

Other than disabling the clock, no changes were made in the transfer switch. The only changes on the generator were to replace a blown fuse (checked all with an OHM meter) and adjust the RPM's to get 60.5hz and voltage from 240V to 220V.

Trouble shooting in the manual says call Dealer if gen set starts but does not assume load.

Any suggestions?
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Old 01-05-2018, 01:33:37 PM
hoghunter69 hoghunter69 is offline
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Default Re: OTCU 150C Not Transferring from Street Power

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Old 01-05-2018, 01:33:47 PM
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Default Re: OTCU 150C Not Transferring from Street Power

If source 2 is not showing available. It will not transfer because it has no where to transfer to. Try resetting the calibration adjustments for source 2.
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Old 01-05-2018, 01:42:56 PM
Wayne 440 Wayne 440 is online now
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Default Re: OTCU 150C Not Transferring from Street Power

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Originally Posted by hoghunter69 View Post
...voltage from 240V to 220V...Any suggestions?
Set the generator voltage back to "240", and your problem will likely be solved.
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Old 01-05-2018, 03:04:55 PM
hoghunter69 hoghunter69 is offline
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Default Re: OTCU 150C Not Transferring from Street Power

Wayne and Billy - I was just reading the manual to see if there was anything I missed. In the IT world we go back to what was working which would be to set the voltage back to 240.

Two questions come to mind- why does Source 1 show not available even though utility power is there and the annunciator panel shows it's ready and connected? The panel shows emergency power is available but the source module says it's not. With the voltage now at 220 (91% of 240) and my pickup around 95% would this be the reason?

Based on your feedback, drop-off and pick-up must be calculated on 240v. I believe I need to go back to 240v/61hz no-load with a pickup of 90% (216v) and drop-out around 87% (209v). Would these be acceptable values?
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Old 01-05-2018, 05:18:51 PM
Wayne 440 Wayne 440 is online now
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Default Re: OTCU 150C Not Transferring from Street Power

I defer to Billy's expertise on the subject, since he has worked on more sets than I have walked past. That said, here is my 2 cents-
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Originally Posted by hoghunter69 View Post
Wayne and Billy - I was just reading the manual to see if there was anything I missed. In the IT world we go back to what was working which would be to set the voltage back to 240.
To me, that is a good idea, and the quickest path to "fixed".

Quote:
...why does Source 1 show not available even though utility power is there and the annunciator panel shows it's ready and connected?...
When you set exercise to "load" the switch simulates the absence of utility power, hence Source 1 is cut off internally, i.e. not available.

Quote:
The panel shows emergency power is available but the source module says it's not. With the voltage now at 220 (91% of 240) and my pickup around 95% would this be the reason?
Probably, your newly adjusted output voltage is below pick-up value.

Quote:
Based on your feedback, drop-off and pick-up must be calculated on 240v. I believe I need to go back to 240v/61hz no-load with a pickup of 90% (216v) and drop-out around 87% (209v). Would these be acceptable values?
They would be at my house. Turn the set up to 235-240V and I think you will see the problem go away.

More- out of curiosity, why did you decide to turn the set voltage down to "220" ?
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Old 01-05-2018, 05:29:22 PM
hoghunter69 hoghunter69 is offline
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Default Re: OTCU 150C Not Transferring from Street Power

Figured better under than over. Since the genset has only supplied emergency power twice in 5 years it's not like it's going to ruin anything with higher voltage. Electric items actually run better at the end of the range so it make sense to turn it back. Besides, if the set fires up during A/C season, the voltage will drop a few volts anyway.

Plan to make the changes Saturday morning when the neighborhood is awake.
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Old 01-06-2018, 04:45:34 AM
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Default Re: OTCU 150C Not Transferring from Street Power

If you turned the voltage down. Without resetting the voltage sensor. It will confuse the system. Testing with load will turn off source one. But if source 2 is not on it has no where to go to. I would return it to the 240 setting. It will not hurt anything.
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Old 01-10-2018, 11:45:34 AM
hoghunter69 hoghunter69 is offline
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Default Re: OTCU 150C Not Transferring from Street Power

Thanks guys. Set the voltage back to 240v/60.5Hz, recalibrated Source 2, picked up as it should. Hope this is the last of my problems for awhile. I'll keep an eye on the belts, make sure the over-rev is not rusted and check the hoses. I should be good to go.
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