Level Switch Listing Requirements

[nhee2]

I have to install a liquid level switch (float type, similar to https://www.gemssensors.com/level/single-point-level-switches/float/side-mount/alloy) in a vessel.

The interior of the vessel could see natural gas/combustible atmosphere.

The exterior of the vessel is in a non-classified location.

I am thinking that if the switch is hermetically sealed such as the gems units referenced, then no additional classification would be required since the electrical portion of the equipment is not in the combustible atmosphere.

Does this sound right?

 

[tom baker]

Its not really my area but I know even with sealed float switches in a sewage wet well we use IS relays.
I suspect the sealed switch doesn't change the requirements...

 

[petersonra]

I have to install a liquid level switch (float type, similar to https://www.gemssensors.com/level/single-point-level-switches/float/side-mount/alloy) in a vessel.

The interior of the vessel could see natural gas/combustible atmosphere.

The exterior of the vessel is in a non-classified location.

I am thinking that if the switch is hermetically sealed such as the gems units referenced, then no additional classification would be required since the electrical portion of the equipment is not in the combustible atmosphere.

Does this sound right?

I don't see where it says these switches are hermetically sealed. If they were they would be labeled as suitable for C1D2.

If the switch contacts are in the non-classified area, I think you don't need to do anything.

Having said that, you might be in the netherworld of the need to have a double process seal which I doubt these have.

 

[Hankj]

I actually called Gems to talk about this earlier this week. I was specifically asking about the LS-52100's. In my case, I will have my float switch in a tank of pure flammable fluid (shouldn't be any air/combustible mixture) but the outside of the tank will be CID2. After I got through the wall of non-technical customer service folks, it was explained to me that the switch itself is the only part hermetically sealed, not the electronics, as you have stated. He tried to point me towards using a barrier or buying the explosion proof model. For us, we've always used the barrier with these but I'm trying to vet out CID2 solutions, rather than D1.

I spoke to a guy named Christian. He seemed fairly up to speed on the codes and said he'd be happy to field any other questions I had. So, maybe you can call and talk to him.