Testing of vaccum circuit breakers

[mvs]

What standards govern the testing of a horizontal, draw-out type, 2000A, 35kv, indoor, vaccum circuit breaker used in metal-clad switchgear? What specific production testing data should I have received from the manufacturer? What field tests should I need to see performed on these breakers?

 

[rhatcher]

You should have received an instruction manual with the breaker. If not, the supplier or manufacturer should provide one to you. Whether or not production test results are provided depends on the manufacturer unless you specify it at the time of purchase. The instruction manual should include specifications for field testing of the breaker.
For vacuum circuit breakers, field testing consists of measuring contact wear, contact resistance, insulation resistance (phase-phase, phase-ground), open contact insulation resistance (line-load, otherwise known as vacuum integrity check), and operational tests of the mechanism and the mechanical interlocks. At a minimum you will need a DLRO and a hi-pot (and some knowledge of such testing...). Most of this work is contracted to outside specialist or in larger organizations delegated to in-house specialists. Contrary to the idea held by some (including this forum), an instruction manual or a good reference alone is not enough to properly understand and perform this type of work.

As a matter of curiosity, can you provide the nameplate information for the breaker in question? I am (admittedly) not directly familiar with switchgear above 15kV and find the idea of metal-clad, indoor, 35kV switchgear as somewhat unusual. Based on the ratings you provided it seems that it would be quite large and (the enclosure) built like a tank (meaning that it is constructed of very strong materials).

 

[Looker]

The hi-pot that you mentioned. Would it be sufficient to hi-pot the breaker for 1 min. at 60kv or is there another hi-pot test that needs to be performed ie. a test of longer duration, with a controled voltage rise over a certian time period in order to track the amps? Would this hi-pot need to be AC or DC and do you have the location of the references to support this?

 

[joan271273]

Please review NETA Acceptance Testing Manual as this is approved by ANSI .

 

[jbartos]

Suggestions: Try
1. ANSI/IEEE C37 "Switchgear Set"

http://www.ieee.org

2. GET-6600E "Power/VAC Application Guide"

http://www.ge.com

 

[don01]

for Rhatcher,
hi, just as a comment, I recall during my apprenticeship testing and over hauling 33kV breakers which were metal clad oil bath monsters with the loudest closing "bang" imaginable. They scred me sh**less many a time when working in the area.
They were made of cast iron and EE brand (English Electric Co.). PS Noah used them as anchors on the ark. The dimensions were about 1.5 to 1.8m wide about the same in depth and about 2.5 m high the top 1m being spring and control cct.

They were also used on a siemens 66kv alternator.

Regards Don

 

[don01]

hi me again
Just to correct myself that alternator couldn't have been 66kv
There was no trani between it and the distribution system for the plant

I must be drinking again (or just getting old)

Sorry Don