Emerson XM670, Инструкция по установке и эксплуатации

Страница: 40 / 57

34 • XM679K I&O Manual 026-1218 Rev 4
20.1.Keyboard Display
CX660
The XM679 board can also operate without a

keyboard.
20.2.Synchronized Defrost
The synchronized defrost (also called master-slave
functioning) allows the user to manage multiple

defrost from different boards connected through the
LAN connection. In this way, the boards can perform
simultaneous defrosts with the possibility to end them
in a synchronized way.
Follow the next steps to create a LAN connection,
which is a necessary condition to perform

synchronized defrost.
1. Connect a shielded cable between terminals -38 and
+39 for a maximum of 8 sections.
2. The Adr parameter identifies each electronic board.
Address duplication is not permitted. In this case,
the synchronized defrost and the communication
with the monitoring system is not guaranteed. (The
Adr is also the MODBUS address). For example, a
correct configuration would be:
If the LAN is well connected, the green LED will be
ON. If the green LED blinks, then the connection is
wrongly configured. The maximum distance allowed
is 30m.
20.3.Sensors for Superheat
Control
Temperature probe: Pb6
terminals [19]-[20]
without any polarity.
Select the kind of sensor
with P6C parameter.
Pressure transducer: Pb5
terminals:
[21] = input of the signal
[22] = Power Supply for 4
to 20 mA transducer
[20] = GND
[23] = +5Vdc power
supply for ratiometric
pressure transducer
Select the configuration of the transducer with

parameter P5C.
20.4.Analog Output
The analog output is located near the terminal [39] on
a 2-pin connector. The output can be used to control
anti-sweat heaters through a chopped phase controller
XRPW500 (500 watt) or family XVD or XVK.
1. Terminals -34 and +35
2. Use twisted shielded cable AWG 18 or less in case
of long distance.
3. Keep at a maximum distance of 30m.
Figure 20-1 - Synchronized Defrost
• Selectable between 4
to 2mA and 0 to
10Vdc.
• Use CABCJ15 to

perform the

connections.