P&B MPC2000D Manual page 14

Local/Remote (74,73)
This contact allows control of the MPC2000D to be switched between local control ( via Start A and Start B Input
Terminals (68,67-66,65)) or remote control either via the direct wired PLC inputs or via the RS485 serial link . It is
also only possible to reset the MPC2000D after a fault from the front panel without authorisation if the MPC2000D is
in the Local control mode.
PLC/Serial Port (72,71)
This contact allows the user when in Remote mode to accept either the direct wired PLC control A and B inputs
(61,62 and 59,60) or commands from the RS485 Serial Port for control of the MPC2000D.
Authorise Key (29,30)
When this input is open it prevents unauthorised access to alter the parameter settings of the MPC2000D. All settings
can be viewed via the LCD display irrespective of the state of this input. However with the input open, an attempt to
adjust a setting will result in the " Unauthorised Access" message being displayed. In addition this input can be used
to restrict fault and alarm reset, if the Auto and Panel reset options of protective functions are disabled a fault can
only be reset from the panel if the authorised input is closed.
PLC Reset (70,69)
Closing of this input resets the unit after a fault, only when PLC mode is selected via the PLC/Serial Port input,
Remote mode is selected via the Local/Remote input, PLC Control A & B are in stop and provided the PLC reset
option is enabled for the particular fault in the Tripping Logic settings.
PLC Control A (61,62)
Closing of this input starts the motor via the contactor A output provided Remote mode is selected via the
Local/Remote input and PLC mode is selected via the PLC/Serial Port input. The motor will continue running
provided the input remains closed. Opening of the input will stop the motor.
PLC Control B (59,60)
Closing of this input starts the motor via the contactor B output, ie Reverse or Low Speed provided Remote mode is
selected via the Local/Remote input and PLC mode is selected via the PLC/Serial Port input. The motor will continue
running provided the input remains closed. Opening of the input will stop the motor.
Serial Port (+ve = 55, -ve = 56, Shield = 54)
The Serial Port utilises a half duplex RS485 protocol allowing up to 32 MPC2000D's to be daisy-chained together
with a single shielded twisted pair cable . Refer to the section 'MPC2000D Communications for full details on the use
of this feature.
Speed Switch (3,4)
This input is used when the safe stall time of the motor is less than or equal to the normal run up time of the motor, in
which case the thermal overload feature will not provide adequate protection against stalling. Connection of a motor
speed switch, open when at high speed and closed when at low speed or standstill enables the MPC2000D to enable
or disable the locked rotor characteristic which is given under the Stall Time Factor setting.
Contactor A and B Status (81,82,83,84 77,78,79,80)
These status inputs from the contactor allow the MPC2000D to determine and show via the front plate LED's the
status of both the A and B contactors.
Use of both normally open and normally closed contacts also provides protection against 'Control Circuit Open' (
when MPC2000D start command is not confirmed by these inputs) and 'Welded Contactor ' (when MPC2000D stop
command is not confirmed by these inputs ) if enabled in the Tripping/Alarm settings page.
MPC2000D Issue 2 22/4/98 Page 11