I need to interface ESD valve 24VDC, 10 W solenoid valve to my control room. The bottle-neck is distance, which comes to around 4 Kilometers. There are only 2 valves. Due to large distance, my cable size will go in to at least 35mm2. I tried to have a solution by a remote I/O, which can be powered by 230 Vac & Peer-Peer link with main ESD system. As per my ESD vendor (I don't want to disclose the name ) he requires at least 230Vac 10A power to operate his remote system, which is again ending up in large cable sizes.

Can anybody suggest a suitable method for this situation? My SIL requirement is SIL-2. Can any system specialist suggest me a solution?

 

Use low power solenoid valve e.g. ASCO Red Hat II.

As per Vendor's information:

Min. pull in current : 0.042 A
Min. pull in voltage : 20.3 V

ESD output is 24 V, so you have 3.7 V available for the cable drop.

Therefore, L x R x 0.042 = 3.7

Where L = cable length = 4 x 2 = 8
R = cable resistance per km

R= 3.7/0.042x8 = 11.01 ohm/km

Any 2.5 mm2 cable will have resistance approx. 8 ohm/km.

So 2.5 mm2 cable with low power solenoid should solve the problem.

 

Thanks for the reply. But I think the Red Hat II is pilot operated solenoid valve. I am looking for direct operating solenoid valve. Is any model available with low power rating in direct acting solenoid valves?

Regards,

Das