Air Circuit Breaker Brand: ABB

The motor charges the spring, which is held in that position by a latch. This latch needs to be released to close the ACB. You can do it manually or by the shunt closing release remotely. Since the ACB has a motor for remote spring charging, and a shunt release for remote tripping, it is logical to have a shunt closing release.

Ashburn,VA, USA?

Think about it. You can easily charge the spring manually using the handle provided on the ACB. You can push the "Close" button manually to close the ACB. You can push the "Trip" button to trip the ACB. (In its capacity as a protective device, the ACB will automatically trip anyway in the event of any overcurrent). All these actions you can do while standing in front of the ACB. If you spend good money to fit a motor to charge the spring, it is almost mandatory to use the remote closing release to close the ACB remotely. Having fitted these two, it makes sense to use a shunt release to open ACB remotely too. As has been said by PeterT, it is safe too.

''it is almost mandatory to use the remote closing release to close the ACB remotely''

I beg to differ with the above statement. Even if the circuit breaker is provided with the spring charging motor, there is no harm in closing the circuit breaker locally through a Trip-Neutral_Close (T-N-C) switch which is generally mounted on the breaker panel.

In HT application (6.6 kV and onwards) a Control and Relay Panel (CRP) is provided for remote closing and tripping of the circuit breaker due to safety reasons and the TNC switch is located on the CRP.

ACB, however, can be switched off remotely through relay contacts used in the tripping circuit for interlocking purpose or manually through local T-N-C switch for shut down purpose. In case of fault i.e under voltage, over current, earth fault etc. the circuit breaker will trip automatically through contact of the master trip relay used in the tripping circuit of the breaker.

You are of course entitled to your opinion. This is LT, and the breaker in question is ABB Emax. Very easy to charge the spring manually. So, no point in having an expensive motor to charge the spring, if you have to come to the breaker to push a button to close it. Makes more sense to have a remote close option. In all my years with ABB, i never saw only a motor being ordered, it was always along with a closing coil.

ABB sells everything separately, the ACB, the shunt trip (open release), closing coil (close release). Motorized ACB means you can fit the closing coil for remote circuit operation but it doesn't come with it if that's what you're asking.

thank you for the reply, yes, abb sold it separately, i just want to know if the acb is motorized and contain shunt opening release does it required to put shunt closing release?

Only if you want to close it electrically (remotely) rather than by pushing the manual closing button on the breaker while standing in front of it. I wouldn't recommend that, in today's safety-conscious world. Get the electrical closing option.

Depends on your application, so if you want to be able to remotely close the breaker then yes the closing coil is a must, otherwise, you don't need it.