MAN-00112 R 2.0 - EasyGrid Base User Guide
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5.3 Analog output
Analog outputs provide a means of transmitting temperature data
directly from the unit to an external data-gathering system or
monitoring equipment. The monitor provides one analog output
for each temperature channel present in the unit.
The EasyGrid Base 4-20mA outputs are of type 3L, non-isolated,
according to ISA-50.1-1982 (R1992)
The power supplies for the 4-20mA output is internally connected
in the EasyGrid Base. Because of that feature, only two wires are
required to realise the connection to the receiver.
FISO recommends a shielded twisted pair. All the EasyGrid Base 4-20mA outputs negative terminals are
internally connected to the power supply ground and that ground is internally connected to the system GND
at the M5 GND stud (bottom left of the EasyGrid Base case).
The cables shields must be grounded at only one end, we recommend to connect-them to the EasyGrid Base
M5 GND stud.
In order to avoid ‘’ground loop’’ errors, the EasyGrid Base 4-20mA outputs shall be connected to floating
receivers, isolated receivers or have an isolator in the loop.
FISO recommends an input resistance of 250 ohms for the 4-20mA receivers. The maximum total resistance of
the loop (including wire resistance) should be less than 800 ohms.
