68 Electrical design and installation
Manual Power Quality Filter PQFS
Note that in a multi-unit filter system in which more than one master system is present,
the digital inputs of all masters have to be set up and cabled in the same way to obtain
full redundancy.
Two connection approaches exist:
−
The first approach is to use one digital input for the start function and the second
digital input for the stop function.
shows the PQF-Manager setup for the
input considered and the resulting effect when applying voltage to this input.
Table 30: Filter behavior as a function of the PQF-Manager settings for local start/stop and
using 2 digital inputs
PQF-Manager setup for
digital input
Vlow applied to digital
input
Vhigh applied to digital input
Edge ON
No effect
Filter starts on rising edge
Edge OFF
No effect
Filter stops on rising edge
Remark: Vlow = 0 Vdc, Vhigh = 15-24 Vdc
When using the Edge ON function the filter can only be switched on by applying
voltage to the digital input considered. It is therefore recommended in that case
to configure and cable the second digital input as Edge OFF. Refer to
Section
for guidelines on how to set up the digital inputs according to the
function required.
The electrical requirements of the digital inputs are as discussed in
Section 4.5
shows a cabling diagram for implementing a start function on the first
digital input and a stop function on the second digital input.
External
stop
push
24 Vdc
external
supply
+
-
1
(a)
2
(a)
3
(a)
4
(a)
PQF-Manager
Digital input 1 (15-24Vdc)
Digital input 2 (15-24Vdc)
Remark:
(a)
Left hand terminal block when looking from rear, counting from top to bottom
External
start
push
Figure 47: Cabling diagram for implementing start on digital input 1 and stop
on digital input 2
