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Installation and Operation Manual for Inverter RPI M50A_12s V1 EU EN 2017-03-09
5 Planning installation
5.8 Connecting a data logger
The inverter can be connected to a data logger via RS485, e.g.
for monitoring the PV system or changing the inverter settings.
Multiple inverters can be connected in series to a data logger.
Note the following recommendations for ensuring a stable data
connection.
Connecting a single inverter to a data logger
► Switch on the RS485 termination resistor.
► Lay the cable with a suitable clearance to the AC and DC
cables to prevent interference in the data connection.
Connecting multiple inverters to a data logger
► Switch on the RS485 termination resistor at the last inverter
in the chain.
► If the data logger does not have an integrated RS485 ter-
mination resistor then also switch on the RS485 termination
resistor at the first inverter in the chain.
► Switch off the RS485 termination resistor at all other invert-
ers in the chain.
► A different inverter ID must be set at each inverter. Otherwise
the data logger cannot identify the individual inverters.
► Set the same RS485 baud rate at all inverters.
► Lay the cable with a suitable clearance to the AC and DC
cables to prevent interference in the data connection.
Cable requirements
● Shielded twisted-pair cable (CAT5 or CAT6) with solid con-
ductors
● Cable diameter: 5 mm
● Wire cross-section: 1 mm
2
5.9 Connecting an external alarm unit
The inverter has two multifunction relays allowing connection of
an acoustic or visual alarm unit to each.
An event can be assigned to the dry contacts on the inverter dis-
play after commissioning, see “8.4.6 Dry contacts”, page 98.
Event
Description
Disable
The function is disabled.
On Grid
The inverter has connected to the grid.
Fan Fail
The fans are defective.
Insulation
The insulation test has failed.
Alarm
An error event message, fault message or
warning has been sent.
Error
An error event message has been sent.
Fault
A fault message has been sent.
Warning
A warning message has been sent.
The default setting for both relays is
Disable
.
Cable requirements
● Shielded twisted-pair cable (CAT5 or CAT6) with solid con-
ductors
● Cable diameter: 5 mm
● Wire cross-section: 1 mm
2