Pilz PSSu E S 2AO I - Manual (Page 25)

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4-9
4.2 Configuration
4 Function description
4.2.4 Switch-on value
Switch-on value 4- ][Funktionsbeschreibung_BA_Konfig Einschalt ST-Aus 2xI
When the PSSuniversal is switched on, the output assumes the switch-
on value until the module receives data for the value of the output. You
can configure the outputs per channel with the manufacturer switch-on
value (default) or you can use a freely definable user switch-on value.
The manufacturer switch-on value is:
 0 mA for the current range 0 … 20 mA and
 4 mA for the current range 4 … 20 mA.
If the module does not receive any data from the module bus for 50 ms,
the outputs are reset to the switch-on value.
Switch-on values are entered in the system software as decimal vaues.
With default scaling, the decimal value (n) is calculated from the ana-
logue value at the output (I
Start
) as follows:
 Current range 0 … 20 mA:
n = 32 767 * I
Start
/ 20 mA
 Current range 4 … 20 mA:
n = 32 767 * (I
Start
– 4 mA) / 16 mA
example:
 Switch-on values as an analogue value at the output (I
Start
):
– Switch-on value for channel 1 is to be 8 mA.
– Switch-on value for channel 2 is to be 15 mA.
 Entry in the system software at
Current range 0 … 20 mA:
– Switch-on value 1 corresponds to 13 107
– Switch-on value 2 corresponds to 24 576
 Entry in the system software at
Current range 4 … 20 mA:
– Switch-on value 1 corresponds to 8 192
– Switch-on value 2 corresponds to 22 528
The relationship between the switch-on value and the actual current at
the output is dependent on the scaling. The module sets the current,
which corresponds to the switch-on voltage after scaling. Please refer
to the "Scaling" section in this manual.