Hello, I have a circuit that will need to return connected hardware to a default state if power is lost. The hardware can handle continuous voltage, so I’m thinking a simple solution would be to use a battery to provide that fallback power source. To avoid draining the battery, I’d like to connect it through a relay on the...
Thanks, I don’t think there are any external settings for the power supply, but it does provide a few more volts than I strictly need. Toggling a single relay hasn’t caused me any issues in the limited testing I’ve done. A momentary drop to as low as 5V should be perfectly fine, although, looking over the specs for my components, I see I’m getting dangerously close to the upper limits for the power supply’s current rating. I’ll have to look into connecting 2 supplies in parallel (or getting a larger supply) I suppose.
I haven’t worked with battery backups yet, so I was thinking it would be best to keep that element simple to minimize potential issues like a trickle charge draining the battery unexpectedly, or damaging the battery from overcharge. The minimum requirement is just to ensure the hardware (a motorized ball valve) returns to a closed position if power is lost. The battery needs to provide at least 9V to power the motor, so I could use a 9V (or a few smaller cells in series) to keep it below the 12V supply.
With your solution using a diode on each voltage source, would there be any risk of a trickle charge draining the battery unexpectedly if the battery? If so, in that configuration I’d need to do more research and figure out how to use a BMS, rather than an externally recharged or disposable cell.
Thanks, that’s good to know! The datasheet doesn’t seem to include the word “duty” anywhere, so I think that must have been omitted. Ostensibly that means the maximum duty cycle is unlimited, but I don’t have enough experience here to say that with any confidence.
I’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).
Continuous operation of a general purpose relay?
Hello, I have a circuit that will need to return connected hardware to a default state if power is lost. The hardware can handle continuous voltage, so I’m thinking a simple solution would be to use a battery to provide that fallback power source. To avoid draining the battery, I’d like to connect it through a relay on the...