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8 Connection of external sensors
and alarm systems
The expansion port is a multi-function interface for connecting external sensors and
alarm systems.
ATTENTION!
Risk of damage to the device!
The interface carries active signals. Use caution during wiring and observe
the specified limit values! SolarMax Produktions GmbH is unable to accept
liability for defects or malfunctions of the MaxWeb XPN or connected devices
resulting from improper wiring, the failure to observe limit values or the use
of devices not approved.
8�1
Connection options
The expansion port has the following connection options:
■
■
Analogue input for an irradiance sensor with 4…20 mA current loop
■
■
Analogue input for a temperature sensor with 4…20 mA current loop
■
■
Two inputs for switching contacts of external alarm sensors
■
■
Four potential-free status signalling contacts, e.g. for reporting malfunctions to a
higher-level operations control system or a visual display
■
■
Six inputs for connecting a radio ripple control receiver (option MaxRemote)
■
■
S0 interface for energy meters
8�2
Irradiance and temperature sensor
Please note the following when connecting sensors for irradiance and / or temperature
measurement to the expansion port:
■
■
The distance between the sensor and the MaxWeb XPN should not exceed 50 m. For
larger distances, the auxiliary MaxMeteo module is required.
■
■
The sensors can be supplied via the integrated 15 V
DC
/ 0.5 A power supply at the
expansion port, if required.
■
■
The precision of the measuring inputs is approx. + / – 5 % of the full-scale volume
(measured at 20 mA). Add up the measurement errors of the sensor in order to deter-
mine the overall accuracy.
■
■
Only sensors with a 4 … 20 mA linear measuring signal are suitable for the meas-
uring inputs (e.g. irradiance 4 mA = 0 W / m2 20 mA = 1200 W / m
2
).