ARDETEM PECA 30 - Page 32

PECA 30 / 30 E : programming-configuration
32
ARDETEM
electrical COS centred on 0
: the COS sign will indicate the load nature (capacitive or inductive)
Example : you measure a network with a COS compensation by capacitors, the load nature is inductive, but if
you compensate too much, you can get a capacitive load. The COS will oscillate round +/- 1.
4-20mA output for a COS between -1 and +1 :
20mA
The COS oscillating round +/-1, the current
output leaps from 4 to 20mA.
12mA The use of a needle meter is impossible,
but the linear transfer function allows
the use of a digital indicator on the current
output.
4mA
-1 0 +1
capacitive load inductive load
To avoid the leaps from 4 to 20mA, use the configuration bellow :
electrical COS centred on +/-1
: the COS sign will indicate always the load nature (capacitive or inductive) but
the current output will be centred on a +/-1 COS.
Example : with the above same example, you program the 4-20mA output for a COS witch range from -0,5 to
+0,5.
20mA 12mA
capacitive inductive
-1 +1
COS
4mA -0,5 +0,5 20mA
4mA
When the COS oscillates between +/-1, the
-1 -0,5 0 0,5 1 current output stay round 12mA.
The transfer function, non linear, prevents
the use of a digital indicator on the current
output.