Safety First - Tec Trek Web Site

Tip of the Week

NOW FOR THE NEWSLETTER

OUCH!!!

This newsletter will be devoted primarily to safety when working on Fire Control Systems. A recent phone call was received from a technician who had the unfortunate experience of a shock to his system without the use of a defibrillator.

The images below are self-explanatory.

However, the image below, with the exception of a large gauge wire is not so discriptive. As he learned the hard way.

The above is a standard 24VDC coil, 4 pole DPDT,form C relay. what is not known is what are we switching through the contacts. When dealing with electricity/electronics never assume anything. Even with drawings, you have no idea what is original and what may have been changed/modified from the systems initial inception. In this case, a functin for HVAC shutdown has been added, meaning High Voltage is being switched through a set of contacts on the relay. OUCH!!

For under $20.00, this no contact voltage tester can save you alot of grief and pain, not to mention potential damage to equipment.

So based on this, here are some things to consider.

As with all test equipment, verify performance on a known circuit before use.

Label any potentially dangerous circuits.

Trust no one or drawing.

Verify all live circuits yourself and remove power if possible.

As with any switching device, always be aware of the contact amperage rating, both inductive or resistive.

It is never a good idea to use relays on the Fire Control Panel or specialty relay module for swithing of high voltage. Relays are cheap, Panels and Modules are not.

The individual on the receiving end of this newsletter, after changing his shorts, is just fine, and alot wiser

If you require more information regarding the terms and explanations above, contact me by email or phone for assistance.

The above information is covered in the following Tec Trek class segments: Awareness Training (FG-01A), Basic Technical Training (FG-01)

For more information regarding training schedules and course curriculum, please visit our Web Site at www.tectrek.org

Or Contact Todd Olivier at (337) 298-7959.

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Email: fto@tectrek.org