Model MCX-32
Model MCX-32 Instruction Manual
Rev.2.3
Page 6 of 49
3.2 Power Connections
The Model MCX-32-N4X controller can be powered by 110/220VAC, 20-30VDC or both. An internal power
supply is available for the MCX-32-N4X that converts 110/220VAC to 24VDC (up to 5Amps) and can power
up to 32 sensors and any associated I/O modules. The MCX-32 controller can also be powered by an external
DC source that meets the input requirements of the unit if AC power is not available or desired.
NOTE:
The power supply for the MCX-32-N4X controller can power up to a maximum of 32
sensors and any associated I/O modules even though the controller is capable of
communication with up to 64 devices.
An additional power supply will be required if
powering more than 32 sensors.
NOTE:
The MCX-32-N4X controller can accommodate only 16 I/O modules. Any additional
modules required will need to be mounted in a separate enclosure by the customer.
3.2.1
AC Power
Connect 110/220VAC input wiring to the terminals labeled “VAC (L1)”, “NEU (L2)”, and “GROUND” (See
Figure 2). The power supply for the MCX-32-N4X is capable of handling AC inputs from 100-240VAC, 50-
60Hz without degradation.
3.2.2
DC Power
For optional external DC power input, connect 20-30VDC to the terminals labeled “24VDC” and “DC Comm”
(See Figure 2). This input can be used for primary power or back-up power in the event of an AC power
failure. The DC input voltage should be capable of delivering at least 5 Amps of current to the load (120
Watts @ 24VDC). This voltage can come from an external 24VDC supply or a battery back-up. If batteries
are directly connected to this input, the unit has the ability to provide the necessary battery charging voltage to
the batteries.
See Section 6.3.9 Power Management Screen for setting up the charging voltage for the
batteries.
NOTE:
The supply of power should be from an isolated source with over-current protection
as applicable. The input voltage range must be between 20-30VDC.
4.0
I/O Connections
There are two distinct RS-485 ports utilized in the MCX-32 controller labeled “RS-485 PORT1” and “RS-485
PORT2” (See Figure 4). These ports are both connected to the primary Modbus
™
and can be utilized for both
sensors and I/O Modules.
Each port has three discrete input terminals labeled “A”, “B” and “Shld”
corresponding to the RS-485 wiring. Also available are two output terminals to provide 24VDC power to
external RS-485 devices. RS-485 wiring with power should consist of a two conductor, shielded twisted pair
for RS-485 and two conductor power (General Cable Commodore p/n ZO16P0022189 is recommended). This
power should be used only to power remotely located I/O modules and/or sensors, and should not exceed 3
Amps accumulative for all I/O modules and sensors attached to the controller. (i.e. if there are two modules
mounted in the enclosure that have an accumulative current draw of 0.5Amps, the sensors and/or I/O modules
connected to the output 24VDC should not exceed 2.5Amps.) Refer to the manuals for each module and
sensor for the maximum expected current draw from each device.
NOTE:
The controller must know what port the RL-4 modules are connected to.
