Replacing the SD85 with the S500-A60: An Alternative Solution
Published on
March 1st, 2024
Murphy’s SD85 Solenoid Power Drive Time Delay was recently discontinued.
But with a little engineering, the experts at MurCal were able to help our customers with a replacement.
The Trombetta’s S500-A60!
Here’s some instructions and images to make the transition as smooth as possible:
To replace an SD85 with the S500-A60, you'd wire the following way:
Terminal 1 on the SD85 is dual purpose. It wires to Battery - (Ground) and to the Ground terminal on the solenoid. With the S500-A60, there are separate terminals.
Terminal 2 on the SD85 is equivalent to the RED (Hold) terminal on the S500-A60. This is the low current output that stays on the entire time that the solenoid is pulled in.
Terminal 3 on the SD85 is equivalent to the AUX (+) "ON OR RUN SWITCH" terminal on the S500-A60. This is what tells it to pull in the solenoid.
Terminal 4 on the SD85 is equivalent to the WHITE (Pull) terminal on the S500-A60. This is the high current momentary output from the module that pulls the solenoid in.
Terminal 5 on the SD85 is equivalent to the BAT + terminal on the S500-A60. This is powered all the time.
See the Trombetta's S500-A60 in the store -->
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For Technical Support, Please Call Us At 661-272-4700, Contact Us Or Email Us At Sales@Murcal.Com
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