Strange Readings from Surge Counters

[TSun]

I recently came across a double ended 480 service entance switchboard with both mains closed and the tie open. surge protection is installed on both service entances. Each surge protector is equipped with a surge counter. The surge counter from one substation recorded around 10 surges, the other counter indicated over 300. I reset the counters and checked back a month or so later. I found one counter showing only a handful of surges and one showing hundreds. Both services are supplied by dry type transformers fed from an entirely underground system with multiple levels of surge peotection and some high end meterng that would have picked up any surges on the distribution system. Essentially I can rule out any causes external to the building. The building only has 'typical' commercial building loads, motors, lights, etc... No low voltage pf corection, transformers tapped at nominal. Any thoughts on what could be the cause? This isn't the first tim. I have seen this either. Several other buildings in the area have similar installations and show the same problem.


Thanks for your help.

 

[waross]

Have you considered interchanging the surge counters? That will tell you if there is really are that many surges or if you have a surge counter that is malfunctioning.

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

 

[ghostbuster7]

If there are VFD's or solid state rectifier's or U.P.S. systems in the area on this feed they will generate lots of voltage spikes.

 

[TSun]

There would be many vfds on both services. Why would vfds produce voltage spikes at the service? The only voltage spikes I am familiar with vfds producing is on the output side. They wouldn't show up on the source side.

 

[odlanor]

check surge counter installation. Both must obbey procedure of comissioning.