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KraftPowercon Sweden AB, Hjalmar Petris väg 49, S-352 46 Växjö, Sweden, Tel: +46 470-705200, Fax: +46 470-705201,
www.kraftpowercon.com
6.5
I/O UNIT 2 (option)
6.5.1
General
As an option a second I/O unit can be installed in order to increase the number of alarm relays
from four to eight relays. In possible project documentation the basic I/O unit is usually named –
K1 while I/O unit 2 is usually named –K2.
6.5.2
Power supply
Is normally obtained from corresponding connections of the basic I/O unit.
Connect to input X5:1 “POWER SUPPLY (-)” and X5:2 “POWER SUPPLY (+)”
6.5.3
Measuring inputs
Not in use.
6.5.4
Digital inputs
Not in use.
6.5.5
Digital outputs
6.5.5.1
General
All outputs fitted with relays have floating relay contacts. For the durability of the relay contacts,
see section
3
TECHNICAL DATA
.
6.5.5.2
Alarm outputs
On this I/O unit there are four additional alarm outputs beyond the usual four alarm outputs on the
basic I/O unit. There are named alarm relay E – H.
The outputs' connection blocks are marked C, NC and NO. The significance of this is as follows:
• C
-
Common point for connection.
• NC -
Connection point for normally closed contacts. Closes on alarm.
• NO -
Connection point for normally open contacts. Opens on alarm.
The term “normal” (N) here means resting relays, i.e. idle. We recommend using NO mode. This
increases reliability as any poor contact action or other breaks in the alarm loop give an alarm
indication. To increase reliability still further, all alarm relays have standing current connection,
i.e. closed relay indicates normal condition while a relay that is idle gives an alarm. This means,
for example, that even a broken relay or the absence of auxiliary voltage gives an alarm indication.
Connect the alarm relays as follows:
Alarm relay E:
C ............. Terminal X6:1
NO .......... Terminal X6:2
NC .......... Terminal X6:3
Alarm relay F:
C ............. Terminal X6:4
NO .......... Terminal X6:5
NC .......... Terminal X6:6
Alarm relay G: C ............. TerminalX6:7
NO .......... Terminal X6:8
NC .......... Terminal X6:9
