LS-20 Instruction Manual
00629-53-000
Page 6 of 18
Issue 12 19 January 2021
5
Indications
The shutter has two sets of isolated volt-free monitor contacts which are available on its connector.
For maximum integrity the ‘shutter closed’ contacts are directly mechanically driven by the blade-
they do not rely on opto sensors or other non-contact methods. This means that the blade cannot
open without opening the ‘shutter closed’ contacts.
Each contact set has a common terminal which is connected to either the ‘open’ or the ‘closed’
terminal according to the state of the shutter. Each contact is rated at 100mA resistive load at
30VDC. The two sets of contacts are isolated from each other and from the control circuitry of the
shutter.
These contacts may be used by external circuitry to monitor and indicate the state of the shutter.
The shutter also has two low power indication outputs, one for open and one for closed. These
output 24VDC at 50mA maximum and are typically used to operate LED indicators on remote control
buttons.
The buttons on the shutter illuminate to show the state. A red light means the shutter is open, a
green indicates the safe condition, i.e. closed.
6
Wiring
The LS-20 shutter is supplied with a permanently connected 3m lead terminated in a 15-way high
density ‘D’ plug. The connector makes available all of the various control and indication features of
both the standard and the ‘SIL3’ versions. The pin connections are as follows:
1
0V
2
Monitor Contact 1 ‘Open’
3
Monitor Contact 1 Common
4
Monitor Contact 1 ‘Closed’
5
Monitor Contact 2 ‘Open’
6
‘Open’ +24V output
7
Monitor Contact 2 Common
8
Remote Open C24V Input
9
Monitor Contact 2 ‘Closed’
10
Monitor 24V
11
‘Closed’ +24V output
12
Control 24VDC input
13
Not used
14
Not used
15
Not used
View looking at plug pins
See ‘Detailed Pin Descriptions’ below for more information.
1
6
11
15
5
10
