Low Voltage 24vdc control/RTD wiring

[Strahan]

Hey guys, Can someone help point me in the right direction? I'm in the process of estimating a job that requires the hook up of 24vdc devices and RTD's to the equipment. There is a drop ceiling above all the equipment and I was wondering if I could run the low voltage cabling and RTD cabling in "open" above the drop ceiling through hangers and where I drop through the ceiling transfer it to RMC to protect from physical damage. Just having a hard time pin pointing code section dealing with this. Thanks

 

[petersonra]

Hey guys, Can someone help point me in the right direction? I'm in the process of estimating a job that requires the hook up of 24vdc devices and RTD's to the equipment. There is a drop ceiling above all the equipment and I was wondering if I could run the low voltage cabling and RTD cabling in "open" above the drop ceiling through hangers and where I drop through the ceiling transfer it to RMC to protect from physical damage. Just having a hard time pin pointing code section dealing with this. Thanks

RMC seems a bit excessive unless it is a really bad location. It seems unlikely that an area with typical drop ceilings would need that level of protection. I would think EMT is adequate.

There are some rules about what you can do in the space above the drop ceiling that you might want to review.

One thing you cannot do, although it is very common, is to lay the cabling on top of the drop ceiling.

I would point out that just because the wiring is 24VDC does not mean you can use article 725.

 

[Strahan]

RMC seems a bit excessive unless it is a really bad location. It seems unlikely that an area with typical drop ceilings would need that level of protection. I would think EMT is adequate.

There are some rules about what you can do in the space above the drop ceiling that you might want to review.

One thing you cannot do, although it is very common, is to lay the cabling on top of the drop ceiling.

I would point out that just because the wiring is 24VDC does not mean you can use article 725.

I would never just lay the cabling on top of the drop ceiling. I was thinking of caddy fastener rings. I agree RMC might be excessive. Need to think about that more. Thanks

 

[big john]

...I would point out that just because the wiring is 24VDC does not mean you can use article 725.

I would think 725 would be the most likely article that applies. He needs to look at his RTD and 24VDC sources to determine if they are classified power supplies.

Did you mean 720?

 

[petersonra]

I would think 725 would be the most likely article that applies. He needs to look at his RTD and 24VDC sources to determine if they are classified power supplies.

Did you mean 720?

No I meant art. 725.

A lot of people think that if it is 24VDC it is automatically a class 2 circuit. That is just not so.