Future Design MCT-MC 4.3, User Manual

Page: 13 / 186

MCT-MC
4.3
Wiring - 13 - FDC MCT-MC
3 Wiring
This section describes the methods and precautions for wiring the MC system components.
3.1 Power Requirements
The MC control system touch screen operates on a nominal 24Vdc supply voltage with an allowable range of
11 to 36Vdc. The P41/B42 loop controls can be ordered to operate from either a DC (11-26Vdc) or an AC (90-
250Vac) supply. Do not power the MC controller components and highly inductive DC loads or input circuitry
to other equipment with the same DC power supply used for the MC.
If the MC is installed in an area with poor power quality or frequent power interruptions, it is recommended that
a time delay-on relay be installed in the power supply wiring to all components of the MC. This will prevent
rapid on-off cycling of the MC during brown-out or momentary power interruptions. Rapid power cycling to MC
can cause damage to the electronics and/or loss of data.
3.1.1 Installing the Power-On Delay Relay
Due to the rate at which AC/DC power supplies reach their nominal supply voltage after application of power,
the relay contact of the timer should be installed between the output of the power supply and the power input
of the MC control system components. This allows the power supply output voltage to reach its nominal value
prior to connecting the MC to its output terminals.
WARNING:

Turn off power to the MC before starting installation, removal, wiring,
maintenance and inspection of the MC controller. Failure to turn off
power may cause electric shock, create a fire hazard or cause damage
to the MC.

Emergency stop and interlocking circuits MUST be configured outside
of the MC control system. If such circuits are made through the MC,
failure of the MC control system may cause uncontrollable operation,
damage to equipment or accidents.
CAUTION:

This section presents recommended installation practices and
procedures. Since no two applications are identical, these
recommendations should be considered as guidelines. The system
designer should be aware that devices in control systems could fail and
thereby create an unsafe condition.

Electrical interference in an operator interface can lead to equipment
start-up, which could result in property damage and/or physical injury
to the equipment operator.
If the application requires an operator or attendant, you should be
aware that this potential safety hazard exists and take appropriate
precautions. Consult NEMA ICS 3-304 for more information regarding
safety for the installation of solid-state programmable control devices.