# Killer storms



## RICHARD PES (Oct 6, 2012)

NEED SOME ADVICE ON SENSITIVE CONTROL WIRING TO PLC ANALOG
INPUT CARDS. LAST STORM TOOK UNIT OUT. WHAT PROTECTIVE EQUIP
WOULD BE BEST FOR THIS APPLICATION. RICHARD PES


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## Big John (May 23, 2010)

Put isolated signal conditioners on any channels where wiring runs outside the building, not just the analog inputs. If you get a serious surge these are gonna be sacrificial, but they still save you from replacing the PLC.

Also make sure you have a dedicated surge arrester on each of those loops as close as possible to the I/O. There are a bunch of companies that make these, I'm having a brain fart on who we used, but aim for a clamping voltage under 50 volts.

-John


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## Jlarson (Jun 28, 2009)

Isolators with surge protection at the panel, surge protectors at the instruments, individual fusing of each loop, separate power supply for your analog instruments with surge protection. Make sure your grounding and shielding is up to snuff too and there is not damage.


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