Basler Voltage Regulator

[roydm]

I have been given a couple of 1971 vintage Basler Electric Volts per Cycle Regulators to fix P# 9085300100
As far as I can tell the tapped Toroid Reactor on one is u/s at least it has wildly different Ohms readings from the identical unit on the other making me think there may be a short between turns.
The Reactor P# BE12025 001
Also there is what looks like a Selenium or Copper Oxide rectifier on the unit feeding the winding of a saturable transformer
I called Basler to be told they no longer make parts for these old regulators.

The benefit of any suggestions or experience with these units would be appreciated.

Thanks

 

[waross]

A suggestion; That equipment is 46 years old. Tell your customer to bit the bullet and buy a new regulator.
Virtually all new Automatic Voltage Regulators now have Under Frequency Roll Off built in. With a new AVR with UFRO you may not need a stand alone V/Hz regulator.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[FreddyNurk]

Basler make a new digital AVR, the price is much much more appealing than replacing a unit of that sort of vintage. DECS100 or similar, I think.

If its an SR4 (which it sounds like it isn't, its vintage is well before my time) or similar, some places even make kits with terminals in the same position as the old AVR.

EDMS Australia

 

[roydm]

Thank-you Gents I will approach Basler for a direct replacement.

 

[stevenal]

Check with Beckwith, they may have a suitable adapter panel for their digital control.

 

[waross]

What size generator is this going to be used with?
Is this a voltage regulator or a Volts per Hertz regulator?
I don't know of any modern generic regulators that do not have V/Hz built in as a standard feature.
Stand alone V/Hz regulators for sets below 2 MW have mostly joined the Dodo.
Scotty can comment on larger sets.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[ScottyUK]

Volt/Hertz limiters are always fitted on bigger machines. Normally there's a controller which tries to prevent the V/Hz limit being exceeded and a supervisory trip which operates if the V/Hz limit exceeds the limit. On older AVR's the controller and limiter could be a card or module within a rack. That's how the Brush MAVR and the Westinghouse WTA-300B AVR's were built up, for example. On modern AVR's the functions are integrated into one box. One of the few benefits of the older designs was that they were field-repairable where the newer ones are repaired by replacing the whole module.

 

[waross]

Thanks Scotty.
A long time ago, V/Hz limiters were not common on small diesel machines.
There was a switch to disconnect the AVR until the set was up to speed.
A common failure was a mechanic forgetting to turn the AVR off before running the set at idle for some reason such as checking valve clearance.
The AVR would generally withstand the under Hertz operation of stopping and starting the set, but any length of time at low hertz would let the smoke out of the AVR.
Some operators liked to run at slow speed for a cool down period.
It was just a matter of time until they inevitably forgot to turn off the AVR before dropping the speed of the set and let the smoke out.
It was a great day when AVRs with built in Under Frequency Roll Off came on the market.
While the primary purpose of UFRO may have been to assist in recovery after an overload such as motor starting, the UFRO feature also saved the AVR if the set was run at low speed for any reason.

Bill
--------------------
"Why not the best?"
Jimmy Carter