Hi

I posted recently about spark suppression on an EMR, but have been unable to get a snubber to work, so have decided to try using a SSR instead. I am using this SSR to power a CRT PC monitor and an LED strip light. It seems to be working fine, but I have a couple of novice questions concerning long-term use:

- This SSR is of 'zero crossing' type which I understand is used for resistive loads. I guess the LED light is resistive, but the monitor will be capacitive or inductive? Will long-term use damage the SSR or the monitor/LED light? Is it dangerous?

- Do I need a heatsink? From the quick test I did, the SSR didn't even get warm, but will it gradually heat up over time? I don't know what the inrush current to the monitor is (it has a degaus coil that engages every time it's switched on), but the operational current is no more than 1amp.

I would be grateful if you knowledgeable folk could clear up these points of concern I have. Thank you!

 

A "Zero-Crossing" Switch is easy on everything, including its self.
That's why they were created.

A Heat-Sink is always good insurance against an unforeseen situation,
even if You don't really need it.
The SSR will have to be able to withstand Short-Circuit conditions until a Fuse can blow,
be sure to include an appropriate Fuse, they're cheaper than a new SSR.
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A "Zero-Crossing" Switch is easy on everything, including its self.
That's why they were created.

A Heat-Sink is always good insurance against an unforeseen situation,
even if You don't really need it.
The SSR will have to be able to withstand Short-Circuit conditions until a Fuse can blow,
be sure to include an appropriate Fuse, they're cheaper than a new SSR.
.
.
.

Thank you for the reply. I will fit a heatsink. I am using the SSR inside an arcade videogame machine, which is fused at the mains plug and at the machine connection (5amp fused mains filter, I think). Do I need to fit an additional fuse specifically for the SSR? Thanks again.

 

- This SSR is of 'zero crossing' type which I understand is used for resistive loads. I guess the LED light is resistive, but the monitor will be capacitive or inductive?

They can also be used for inductive loads.
Most off the shelf versions ARE zero-cross switching,
The motor is an inductive load.

 

They can also be used for inductive loads.
Most off the shelf versions ARE zero-cross switching,
The motor is an inductive load.

That's good to know. Thanks.

 

The need for Fusing is a judgment call, which will be based on what You are switching
and the Wiring practices, length of run, and potential of shorts occurring.
I would say that powering a CTR Display qualifies as hazardous.
The Power-Supply being Fused is a good thing, but not necessarily adequate.
The SSR is rated for ~10-Amps, that's good,
your Load might normally surge to ~5-Amps on start-up,
so I'd install a 5-Amp Fuse at the Power-Input to the SSR
just for additional peace of mind.
.
.
.

 

The need for Fusing is a judgment call, which will be based on what You are switching
and the Wiring practices, length of run, and potential of shorts occurring.
I would say that powering a CTR Display qualifies as hazardous.
The Power-Supply being Fused is a good thing, but not necessarily adequate.
The SSR is rated for ~10-Amps, that's good,
your Load might normally surge to ~5-Amps on start-up,
so I'd install a 5-Amp Fuse at the Power-Input to the SSR
just for additional peace of mind.
.
.
.

Good information. Thank you.