Pringle Switches 5

[DTrump]

Should I have any concerns about exercising a 2000 amp main Pringle switch that hasnt been exercised in about 10 years?

 

[dpc]

Not if it is de-energized.

Otherwise, I'd try to get as much load current off it as possible before opening.

Seriously, if there is any way to kill the incoming power before opening/closing, I'd strongly recommend it.

David Castor

http://www.cvoes.com

 

[Zogzog]

Agreed, that is a long time to not have been operated, likely the grease is all dried up and hard, I would expect some issues.

 

[cranky108]

Explain what you are calling a pringle switch.

 

[davidbeach]

Probably a bolted pressure switch manufactured by Pringle.

 

[dpmac]

If you read the instruction booklet that came with the switch the first line is:

"This switch will provide years of trouble free service in the closed position"

If at possible de-energize the feed so you can deal with it in a safe manner should it malfunction.

We get called in to "stand by" many times a year when customers are required to operate bolted pressure switches after a long dormant period. Problems run about 50-50.

Older non stored energy (no springs) switches can be tricky depending on amperage. An older 4000A switch may require 2 men and a boy to close properly.

Be safe.

 

[DTR2011]

really inspires confidence when there is a ground fault relay connected to the shunt trip and it is the main.

 

[DTrump]

Thanks guys, I was going to shut off all of the circuit breakers in the panel first, but I think I will contact the power coompany in regards to "killing" the feed to the service also.

 

[Zogzog]

Be sure to suit up in your PPE if you can't get power off. And be prepared to not be able to re-close the switch. Since you are shutting down you may want to have it tested.

 

[EmergencyPowered]

Throw it hard and mean. Do not be timid. If is a handle operated opening throw it stiff and clean. If is "spring opened" or "shunt trip" style, push the trip button solidly and all the way. It may be hard to push. If electrical shunt trip....expect a coil failure and manually trip if possible! Pringles are "best of breed", but ten years is quite awhile! Good Luck!

 

[DTrump]

All went well, had the power co. come down and de-energize the line side coming in. Threw the switch, made a visual inspection threw it back in and another inspection good to go. Will do this on a yearly basis in the future. The service was installed in 1977.

 

[Zogzog]

I would do more than just open and close it, you should clean and lubracate the mech, test the insulation and contact resisance, and test all the electrical devices for proper operation. A testing company can do all of this for you in about an hour or so.