Control for latching relay
Control for latching relay
(OP)
Hi all,
Please I need help for a little issue.
I have a latching relay in a lighting panel board that should control a lighting circuit. This lighting circuit should be controlled from a push button installed in the site and from BMS. The control circuit should take into consideration an override (priority) for the signal coming from the BMS.
Example: If the circuit lighting was turned on from the BMS command, a person on the site doesn't have the right to turn off the circuit, that means if he pushes the push button, the lighting will not turn off. It remains on.
Please can I anyone help me in the control diagram ?
I have made this little proposal, but I think it needs some modifications.
https://res.cloudinary.com/engineering-com/image/upload/v1432307868/tips/Latching_relay_LUNC_detail_cwip9f.pdf
Thank you in advance,
Kind Regards,
Rami
Please I need help for a little issue.
I have a latching relay in a lighting panel board that should control a lighting circuit. This lighting circuit should be controlled from a push button installed in the site and from BMS. The control circuit should take into consideration an override (priority) for the signal coming from the BMS.
Example: If the circuit lighting was turned on from the BMS command, a person on the site doesn't have the right to turn off the circuit, that means if he pushes the push button, the lighting will not turn off. It remains on.
Please can I anyone help me in the control diagram ?
I have made this little proposal, but I think it needs some modifications.
https://res.cloudinary.com/engineering-com/image/upload/v1432307868/tips/Latching_relay_LUNC_detail_cwip9f.pdf
Thank you in advance,
Kind Regards,
Rami





RE: Control for latching relay
RE: Control for latching relay
Thank you for your kind feedback.
I know my proposal is missing something.
Can you help me to modify it ?
Thank you,
Regards,
Rami
RE: Control for latching relay
It may take a second latching relay to solve the problem with hardware and there will be more failure modes and the reliability will be poor.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Control for latching relay
Thank you for your help.
Connect the push button to the BMS system and handle it in the software.
It may take a second latching relay to solve the problem with hardware and there will be more failure modes and the reliability will be poor.
Kindly can you show me your idea by sketching a control diagram ?
Thank you,
Ragards,
RE: Control for latching relay
This is eng-tips, not eng-we-do-the-work-for-you. We have no idea what hardware you have. You need to design the circuit, and if you want feedback on it, you can post your control diagram sketch.
xnuke
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RE: Control for latching relay
Try this: http://escventura.com/manuals/ab_typicalWiringDiag...
Learn to draw ladder diagrams like those in the above link. It is an essential tool for designing control wiring circuits.
RE: Control for latching relay
RE: Control for latching relay
I'm not sure what a BMS is but I assume PLC to relay controlled with software energizing the relay on or off. Your diagram as you know is poor. May I suggest you use a key lock style light switch for power to the lights this might accomplish what you need with safer results.
Chuck
RE: Control for latching relay
Use two parallel switches (or these latching relays if you wish) to provide the override. If either switch (relay) is on, then the light is on.
LOOK -^
Does this meet the partially defined description of "override"?
RE: Control for latching relay
Now, suppose a person is in the corridor , and he pushes the push button, that should not turn off the light because the BMS signal has the priority over the pushbutton.
RE: Control for latching relay
Repeat.
Bill
--------------------
"Why not the best?"
Jimmy Carter
RE: Control for latching relay
RE: Control for latching relay
RE: Control for latching relay