Inside a Simplex 4208 panel!

Now before anyone starts any accusations, they DID let me take these photos, as the fire alarm system at the K-8 school I attended was being worked on due to a trouble condition on the Simplex 4010 panel, so the panels were already opened up when I saw them. (They’re doing construction/fix-ups to the school this summer, and it’s pretty busy there!) But this is to show inside of the 4208 panel, as it looks a lot more interesting than a 4010 does, and plus there haven’t been any photos of inside an older 4208 up here yet. I’m a little new at this though (I mostly know a bit more about more modern fire alarm panels, and not much about Simplex’s pre-1979 panels…) These pictures show a four-zone 24-VDC Simplex 4208 system…

This is in the top half of the 4208. You will notice a lot of relays and wires inside it. I was surprised to see those circuit board-like things in such an ancient panel, too. There are also TWO coding wheels instead of one. They look like they were set to do 4-4 at one time. I wonder if maybe one coding wheel was for the horns, and the other for the light plates (as I’ve seen quite a few 4207 systems set up so the horns are on Continuous while the light plates would flash.) This doesn’t explain the Slow March Time when I was here, though (that might have been due to the school having a 2001 or 4002 tied into it back then.)

Bottom half of the 4208. I did notice several newer-looking Simplex relays on the right (I think they’re relays, they look the size of it; plus they have the modern Simplex logo on them.) They are either replacing older relays, or they have something to do with the 4010 system (prior to that, they had a 4004 installed in 1998 for the duct detectors and system monitoring.)

My attempt at a shot of the tag inside the panel. For some reason the model number is just “4208,” with no additional letter or number after it like many of Simplex’s 42XX-series panels had (like 4247-2 or something.) The manufacturing date is March 22, 1974, and was custom-built for the school, as many of those 42XX-series systems came with many options and could be designed for a certain place, unlike today’s modern fire alarm panels that come with many of those originally-optional features already included.) It’s definitely not a local system; it was designed to trip a master box when going into alarm mode to contact the fire department, but now this is handled by the 4010.

When the portable was added in 1996 (which has since become permanent ever since the school added 7th and 8th grades), it had its own small ESL fire alarm system (with Wheelock MT-LSMs, ESL smokes and RSG T-bars), but IDK if it still has its own ESL panel. Chances are, the 4010 now controls the portable as well.

Any comments or questions would be appreciated!

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