EOL Resistor gets hot

The 10K ohm EOL resistor on my Simplex 4004 heats up after about 5 minutes. Is this normal? Im not using a resistor provided by Simplex (I got the panel from eBay, and it did not come with resistors).

You might want to use a larger wattage resistor. Ex: 2 Watt 10K resistor, which would dissipate some of the heat. But thats my guess…

Resistors heating up during normal use is expected - resistors reduce voltage and current by converting it to heat. So, some heat is to be expected.
If it’s too hot to touch, or is starting to smell, you may be overloading it.
Most “off-the-shelf” resistors are 1/4 watt, but most fire alarm panels want at least 1/2 watt resistors. I’ve actually had to specify 1/2 watt 4.7kOhm resistors for my 9050-UD system. You might try that wattage on the NAC’s EOL and see if that fixes the problem. You can find 1/2 watt 10KOhm resistors here.

Thanks. I haven’t left it connected for too long (once I noticed the heat), so I don’t know if it gets too hot. I’ll check on that soon, and if it does, i’ll probably buy the 1/2 Watt resistors lol.

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