Electric Fan relay question

BlackFox5.0

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Aug 7, 2000
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Massachusetts
I finally got around to getting a bigger relay, it's a Bosch 75amp I won on ebay for a good price. But I noticed the part number is different than the one on the smithmonte website. Mine is a 0-332-002-150, the website says:

I would recommend the 0-332-002-156 which has the series and parallel clamping diodes and is specified for motor loads.

I looked up my relay and it seems to be the same, only without diodes....

If you go here, you can see mine at the very top, and the one smithmonte recomends below it.
http://www.bpg-inc.com/Power.htm

Will I be safe to run the relay I have? Can't I add diodes to my relay to be like the 156 somehow?
 
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The diodes are a necessity to prevent damage to the computer, radio and other electronic equipment.

The diodes can be added externally, you can get them from Radio Shack. It takes a 1 amp 400 PIV diode, a diode with a higher voltage and/or current rating can be used. The band on the diode goes the positive side of the wiring and the other end goes to ground side of the wiring. The diode is wired across the relay coil. Another diode is wired across the fan power output terminal on the relay in the same manner, band to positive and other end to ground. Make note that if you connect the diodes up backwards, you will make smoke and sparks.
 
Hmm... I only have a diode at the fan end. Like this diagram I made for my brother. Is this bad jkricher? I havn't had any problems with it so far.
 

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