willysmjeeps.com

Hello, I have a Mars 24volt siren on the right fender of my 1955 M38a1. I want to connect it to a switch. I was planning on running a wire directly from the battery positive to a switch and back to the siren. Can anyone tell me what gauge wire to use? Also, I was thinking of hooking the wire from the battery to an auto fuse. I was thinking 20 amps. Sound right? - Thanks, Wally

Wally, Assuming that your M38A1 is also 24V, you need to let folks know two important factors. The amperage draw of the siren and the length of wires you intend to use? With this info you or anyone can look the required wire gauge and fuse size up in a load chart.

Since I am an aircraft mechanic by trade I prefer to use their standard pubs. In this case I suggest FAA Advisory Circular 43.13-IB Acft Maint. Standards, Chapter 11- which covers electrical system repairs and has all the needed charts for calculating the answer to your question.







You can download the needed pages from my photo album. Your siren should have the data plate listing it's part/model number and electrical info.

My photo album with this info is: http://www.willysmjeeps.com/v2/modules. ... _album.php
https://www.faa.gov/regulations_policie ... opicID/114

FAA Advisory Circulars AC 43.13-1B and AC 43.13-2b
You can also download these two manuals free on the FAA web site:

Thanks Wes. Yes, I have a 24 volt M38A1. I don't know the amps drawn by the siren. I'll read what you referenced. -Wally

I could not find any photos showing the Mars S-60 siren with a data plate that listed more than model brand, serial number. You may have to just use an in line amp meter (VOM) to determine the actual current draw of the siren.

Yes. The data plate on the siren doesn't show the amps. I'll try thr amp meter.
Thanks. - Wally