Single phase voltage regulator

[BillyBob2021]

Hello,

Does anyone know what may cause a voltage regulator to get stuck on step -/+16. We have regulators that will occasionally get stuck on 16. We try to place them in Manual and raise or lower them but they won’t budge. They seem to just get stuck on the limiter switch. I don’t understand why it locks out on 16. We end up having to open up the position indicator glass and moving the hands this way.

 

[cranky108]

Moving the hand?
It is a mechanical device, and as all mechanical devices can have problems. A recent problem we had was a stuck brake solenoid. Could be a dirty contact, or a bad controller. Or even a bad voltage sensor.
That all said, I am envisioning a platform or pole mounted device.
What type do you have?

 

[crshears]

How many taps in total? Is tap 16 one below neutral tap [33-tap regulator] or one down from the top [17-tap regulator]?

33-tap regulators often take three times longer to move from neutral tap [17] either up to 18 or down to 16, whereas the watchdog timers are set to the shorter interval of tap changes farther from centre, with the result that tap changes near centre are perceived to take too long to complete and lock out the control circuitry of the automatic voltage regulation scheme.

Bottom line, you may have an electrical problem rather than a mechanical one.



CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]

 

[dpc]

Is the actual regulator mechanism stuck or just the indicator? I can't see how moving the hands of the indicator would make the regulator actually change taps.

 

[Palletjack]

Look on the face and move the limits to 5 or 8%.
Try it this way, see if it’s a stop issue at +-16.

I’m like some others here. How do you get it to move by messing with the clock face?
Just the indicator hands get stuck? If you are wiggling the hands and the regulator starts stepping it’s an electrical problem that could be fixed by restricting the steps.

 

[thermionic1]

Some VR's have the dial indicator on a chain drive that connects to the switching mechanism. I found one a while back that was not properly sync'd, so it was one tap off and causing circulating currents. I imagine if this was the same type, moving the dial may affect a limit switch. Other manufactures have a flexible shaft that drives the position indicator.

VR's & LTC's have a limit switch that kills the motor and prevents damage if the control looses it's mind. If the limit switches are not adjusted properly, that could be the problem. As shown below, the limit switches are normally closed and open when past the limit.

More info is required from OP to have a better idea.

 

[bacon4life]

What model? Moving just the hands by opening the glass would not fix the actual tap position.

I have had the software loose track of the tap position, which then makes the software think the limits are in the wrong spot.

 

[cranky108]

I have seen where the breaking solenoid had a problem, and it would miss a tap. In doing so it would continue, as it does not want to be off tap.