Mircom OpenBAS-HV-NX10 Series, Installation Manual

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Field Wiring
4.6 Field Bus Connections and OpenBAS-ACC-DB9
Figure 22 Field bus connections
Note 1: P3 and COM3 are functional only on OpenBAS-HV-NX10D.
Note 2: Each of the three P ports allow the field replacement of the RS-485 modules with the
OpenBAS-ACC-RS485 optically isolated RS-485 module or OpenBAS-ACC-RS232
conversion module. See section 3.3.1 on page 13.
Note 3: To avoid intermittent communication blackouts, the isolation provided by the
OpenBAS-ACC-RS485 module is highly recommended for noisy environments, and to prevent
damage to the boards in extreme cases, especially if the OpenBAS-HV-NX10 series controller
is inside an enclosure containing high voltage wiring.
4.6.1 OpenBAS-ACC-DB9
OpenBAS-ACC-DB9 is a DB9 adapter which is installed in one of the field bus ports.
24 VAC coil
Install a 36 V MOV surge
protector in parallel with coil of
solenoid to suppress noise.
Table 9 Field Bus Ports
Port Driver Module Functional Optional Driver Comments
COM1 RS-485 Yes Yes
See notes 1, 2 and 3
COM2 RS-485 Yes Yes
COM3 RS-485
OpenBAS-HV-
NX10D only OpenBAS-HV-
NX10D only
Table 8 Surge Protection on Relay Outputs (Continued)
Type of field
device Notes Wiring diagram
24 VAC coil
24 VAC
0 V
C
NO
NC
Controller
COM1
ref1 d1+ d1- ref2 d2+ d2- ref3 d3+ d3-
COM2 COM3