6 replies to this topic

[panagiotis]

Could you please explain me the limit switch and position switch with an example?
Thank you in advance!

[breizh]

Hi ,

Reactor  supplied with liquid 

LSH  to protect the tank from overflow and cut off the feed 

LSL  to prevent cavitation of the pump on low level and stop the pump.

 

Breizh 

[panagiotis]

Thanks for the reply! I would like to ask you what is the difference between level switch and level transmitter?
(I will search also myself, but your answer will be appreciated.)

[breizh]

Hi,

a Level transmitter delivers a continuous reading on which you can assign alarm thresholds ( LAH, LAL ) , LS switches are different technology , for safety purpose , often hard wired .

 

In the case of level transmitter , the alarm thresholds are there to help the panel operators (sound alarms ) to inform them about deviations in the process.  

 

LSH is placed at a level higher than LAH , 

LSL is placed at a level lower than LAL. 

 

Edit : Don't be confused with position switches on ON/OFF valves to inform panel operators about valve open or close.

 

My view.

Breizh 

[latexman]

It is similar to an on/off light switch compared to a dimmer light switch (rheostat).  One is digital, on/off, and one is continuous, dimmer. 

[panagiotis]

Breiz, exactly that is my confusion.
By asking these questions, more things are clarified.
The position or proximity switch is completely different than level switch or temperature switch.

[panagiotis]

Thanks latex man for your reply.