Micromod Micro-DCI: 53MC5000 Multi-Loop Process Controller Installation - Manual (Page 17)

NOTE
Use of a common bus bar is recommended to minimize potential voltage
differences that may occur as the result of ground current loops, i.e.,
potential difference between separate signal grounds, power grounds,
etc.
2.4.2.1.2 AC Power:
Connect the specified line service (110-120, 220-240 V ac, 50 or 60 Hz) to the Controller, as
follows:
1. Connect the phase or hot line (L), via a remote power disconnect switch or circuit
breaker, to terminal "L1".
2. Connect the neutral line (N) to terminal "L2" for 110-120 V ac. Connect the neutral line
(N) to terminal "L3" for 220-240 V ac.
3. Connect Power Common to a good earth ground (#12 AWG wire is recommended).
4. The instrument case shall be grounded by connecting terminal "G" to earth ground at the
source of supply (green/green-yellow ground).
5. All supply connections include surge protection rated at 264 V ac, normal mode, and 275
V ac, common mode to chassis ground.
NOTE
To minimize possible interference, ac power wiring should be routed
away from signal wiring.
2.4.2.2 VOLTAGE INPUT
When the input signal is from a 4-20 mA current transmitter, a precision 250 ohms (+/-0.1%) resis-
tor is required. The resistor tolerance is critical in this case, because the resistor is utilized to accu-
rately convert the current signal from the transmitter (4-20 mA, typical) to a specified analog input
voltage (1 to 5 Vdc). The standard rear terminal board has the appropriate resistors on AI0 and
AI1. If the input signal is already a voltage signal, the resistors should be removed. The optional
Cord Set ITB has the appropriate resistors on AI0 - AI3.
2.4.2.3 CONTACT INPUTS
Two separate contact input signals may be used for system sequencing or control purposes, e.g.,
pump "on" contact. One side of each remote contact must be connected to power common, refer to
Figure 2-5 of this manual and Figure 2-11 of the Instruction Bulletin 53MC5000. The remote con-
tact must provide a maintained closure for at least 0.05 second, to provide the Controller with
enough time to "read" the signal. The user must assign each remote contact to a specific input
(DI0-DI1) as dictated by the particular operation to be performed.
2.4.2.4 CURRENT OUTPUT
Two current output signals are available for transmission to remote analog indicating, recording or
controlling devices. The current output signal, 4 to 20 mA, will vary in direct proportion to the proc-
ess variable being displayed, e.g., volumetric flow rate, mass flow rate, operating pressure, etc.
Observe proper polarity when connecting the remote analog instrument.
MODULAR CONTROLLER QUICK START
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