22 • XM679K I&O Manual
026-1218 Rev 4
11 Electrical
Connections
The XM670/XM679 controllers come with a screw
terminal block to connect cables with a cross section
up to 1.6 mm
2
for all the low voltage connections: the
RS485, the LAN, the probes, the digital inputs, and
the keyboard. Other inputs, power supply, and relay
connections are provided with a Faston connection
(5.0 mm). Heat-resistant cables have to be used.
Before connecting cables, verify that the power
supply complies with the controller’s requirements.
Separate the probe cables from the power supply
cables, from the outputs and the power connections.
Do not exceed the maximum current allowed on each
relay; in case of heavier loads, use a suitable external
relay.
11.1.Probe Connections
The probes should be mounted with the bulb upwards
to prevent damages due to casual liquid infiltration. It
is recommended that the thermostat probe be placed
away from air streams to measure the average room
temperature correctly. Place the defrost termination
probe among the evaporator fans in the coldest place,
(where most ice is formed) and far from heaters or
from the warmest place during defrost to prevent
premature defrost termination.
12 RS485 Serial Line
Each XM670/XM679 controller has a direct RS485
connection that enables the controller to be linked to
a network line that is MODBUS-RTU compatible
with all monitoring systems.
13 How to Use the
Hot Key
XM controllers can download or upload the
parameter list from its own non-volatile internal
memory to the Hot Key and vice-versa through a
5-pin connector. The Hot Key will not change the
Adr
.
13.1.Download (From the
Hotkey to the Device)
1. Turn OFF the controller by pressing the on/off
button
for five (5) seconds.
OFF
will display.
Insert the Hot Key into the 5-pin connector
labeled
HOT-KEY
, and then turn the controller
back ON by pressing the on/off button again for
five (5) seconds. The normal temperature value
will display to indicate the controller is ON.
2. The parameter list of the Hot Key is downloaded
into the controller memory automatically and
doL
will display. After 10 seconds, the controller
will start working with the new parameters.
3.
End
will display at the end of the data transfer
phase if the controller is programmed correctly.
Err
will display if there is an error or failure in
programming.
•
End
= correct programming. This means the
controller will start regularly with the new
programming.
•
Err
= failed programming. In this case, turn the
controller OFF and then ON if you want to restart
the download again or remove the Hot Key to abort
the operation.
4. Remove the Hot Key.
Note: The procedure may fail if the firmware version
and the controller models are different.
NOTE: Maximum current allowed for all the
load is 16A.
