Comment on Continuous operation of a general purpose relay?
trafguy@midwest.social 1 year agoI’m a little new to the terminology, so to clarify, the switching current refers to the amperage across the terminals other than the coil, right? I’m definitely within those limits; I don’t expect to transfer more than ~1/8 of the maximum amperage.
Is there a rule of thumb for the minimum current I should allow across the coil? The only specification I see on the datasheet for coil amperage is that it was tested to failure at 100mA. I don’t think power consumption is too big of a deal with this use case, but resistive heating sounds like it could shorten component life (and even if it’s only a secondary consideration here, I’d still prefer to minimize waste).
empireOfLove@lemmy.one 1 year ago
Yes. “Switching current” is the load current being controlled across the main contacts. I figured you were well within specs, I was just clarifying what typically limits relay duty cycle other than the coil.
Stick to the rated coil voltage in the datasheet or below and you’ll be fine. They set the coil resistance to be within the safe current zone per V=IR at rated control voltage.
Many relays can reliably switch well underneath their rated control voltage depending on their design- there’s a lot of safety factor built in. I’ve had some 12v automotive relays switch successfully at around 5v (by accident, lol). Experiment a bit and you may be able to cut down on waste power
Just be aware that control voltage (coil) and rated switching voltage (load) is often different, since many relays use low control voltages to switch high voltage loads. Don’t confuse the two!