Motorvision Drawout (MVD) Technical Manual - PBSI Group Ltd

MVD TECHNICAL MANUAL
6. MVD Control Inputs.
The MVD offers 12 digital inputs to provide full control and indication for the motor starter. The
supply to these terminals is internally derived from the auxiliary supply which is used to power
the unit.
In order to energise a digital input the terminal should be powered by a voltage which is both
the same phase and magnitude as the live connection.
The condition of all these inputs can be viewed at any time via the Digital Inputs page of the
Data Menu which enables complete wire checking without the need to disconnect or even gain
access to the rear panel wiring.
The 12 inputs are chosen by the user from the list described in the following sections.
Start A and Start B Inputs.
When one of these inputs are closed the corresponding output relay is energised as long as the
Start Setup Sources has been set accordingly (see sections 10.5.1.1.1 and 17), and provided
all other External Faults are in the healthy state. Start A only is used for DOL, DOL Forward,
Star or Low Speed contactors whilst Start B is used for DOL Reverse or High Speed. The
starter settings menu allows these Start inputs to be either momentary, i.e. from push buttons
or maintained, i.e. from PLC outputs not both.
Stop Input.
If this input is open circuited the motor will be switched off and inhibited from starting as long as
the Stop Setup Sources have been set to allow the stop to be active from the remote source.
see sections 10.5.1.1.1 and 17.
Emergency Stop.
This input allows the MVD to monitor the status and provide indication of the state of any of the
external Emergency Stop buttons which are normally directly wired to the contactor closing
circuit. Opening of the input causes a trip with an option to alarm depending on the Protection
Settings. Emergency Stop is only disabled when used for contactor applications, (short circuit
protection is also disabled) when the phase fault current exceeds 9x In.
Contactor A and B Status.
These status inputs from the contactors allow the MVD to determine and show via the front
plate LED's and LCD display the status of both the A and B contactors, also known as Relays 1
and 2. Cont A is the feedback signal for a Start A command and Cont B is the feedback signal
for a Start B command.
Monitoring of these contacts also provides protection against 'Control Open' (when a MVD
START command is not confirmed by these inputs, Cont A and/or Cont B) and 'Welded
Contact' (when MVD STOP command is not confirmed by these inputs). Only when the
Contactor Fault protection is enabled do these ‘active faults’ appear under warranted situations.
Test Mode.
When in the Test mode the MVD will disable Undercurrent Protection, Undervoltage, Single
Phase and Phase Sequence protection functions, as well as the External Faults if set to Disable
in Test.
This allows full functional testing to be performed without the need for voltage or current
injection and will allow secondary injection testing to be carried out on all protective functions
except for those disabled by the feature.
P&B Engineering Issue 1 03/2008 Page 9