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MM200 MOTOR MANAGEMENT SYSTEM – INSTRUCTION MANUAL
CONTROL ELEMENTS
CHAPTER 4: SETPOINTS
Control elements
Auto/manual control
The auto/manual control element manages the auto/manual control mode, consolidates
the start A, start B and stop controls from their various sources, and applies auto/manual,
test switch and permissive supervision.
The MM200 has four possible sources of start A, start B and stop controls:
•
Communications: Controls received over a serial data link - Modbus, DeviceNet,
Profibus and/or Modbus TCP. Communications controls are not differentiated based
on port or protocol.
•
Hard-wired: Controls received typically via contact inputs from a PLC or DCS.
•
Field: Controls received typically via contact inputs from pushbuttons or switches
located adjacent to the controlled equipment.
•
MCC: controls received from the control panel of the MM200.
Communications and hard-wired controls are considered to be auto controls, and are
inhibited unless auto mode is on. Likewise, field and MCC controls are considered to be
manual controls, and are inhibited unless manual mode is on. Each source may also have
a contact input assigned to permissive supervision, which enables that source when on.
Table 4-4: Auto/manual control sources
The MM200 may also be set to always honor stop controls, regardless of auto/manual
mode and permissive supervision (default).
The auto/manual control element also drives a control source active indicator for each
source on the front panel display (if equipped) that shows the user exactly which control
sources have both the correct auto/manual mode on and have their permissive configured
and on.
The auto/manual control element includes non-volatile latches that hold the auto and
manual mode states. Besides supervising controls from the sources, the latches drive auto
and manual indicators on the MM200 control panel. The latches can be controlled either
by an external auto switch contact or by the control panel.
•
When configured for Auto/Man switch contact, auto is on when the contact is closed
energizing the input, and manual is on when the contact is open.
•
When a switch contact is configured for auto/manual, the front panel auto/manual
pushbuttons are inoperative. When no switch contacts are configured, but the
MCC
Auto/Manual Key
setpoint is “Enabled”, the control panel auto and manual keys will
switch the mode between auto and manual.
•
When no input is configured for auto or manual, and the
MCC Auto/Manual Key
setpoint is “Disabled”, both auto and manual modes are set on.
The Auto and Manual modes are temporarily forced to settable states when the test switch
is on.
The following setpoints are available for the auto/manual control element.
Control source
Supervision
Communications
Auto
Comms permissive
Hard-wired
Auto
Hard-wired permissive
Field
Manual
Field permissive
MCC
Manual
MCC permissive