Mtl5526 - Switch Operated Relay - Eaton Crouse-Hinds MTL5500 Series Instruction Manual

6 .2 .7
Two channel, output
The MTL5526 enables two separate IS circuits in a hazardous area to be relay-contact controlled
by two on-off switches or logic signals in a safe area. Applications include the calibration of
strain–gauge bridges; changing the polarity (and thereby the tone) of an IS sounder; the testing
of IS fire alarms; and the transfer of safe-area signals into an annunciator with IS input terminals
not segregated from each other.
The output–relay contacts are certified as non–energy–storing apparatus, and can be connected
to any IS circuit without further certification, provided that separate IS circuits are such that
they would remain safe if connected together.
CH2
STS
CH1
STS
MTL5526
PWR
Figure 6 .16:
Top label
for MTL5526
Table 6 .3:
Switch settings
for modes
36

MTL5526 - Switch Operated Relay

Hazardous area Safe area
1
1
2
3
4
2 5
6
All contacts shown
in normal position
(relays de-energised)
Terminal Function
1 IS relay output 1 (normally open)
2 IS relay output 1 (normally closed)
3 IS relay output 1 (common)
4 IS relay output 2 (common)
5 IS relay output 2 (normally closed)
6 IS relay output 2 (normally open)
8 Relay 1 control +ve
9 Relay 1 control –ve
10 Relay 2 control +ve
11 Relay 2 control –ve
13 Supply –ve
14 Supply +ve
Mode Function
2 ch
Contact/Logic
Input
1in2out
2 ch
Loop Powered
Contact Loop
inputs powered
7
8
IS relay
9
1
Sw4
10
IS relay
11
2
12
13
Vs–
14
Vs+
20 to 35V dc
SW1 SW2 SW3
Off On On
On On On
Off Off Off
1 2 3 4
OFF position
ON position
Control
20 to
35V dc
SW4
On
On
Off
INM 5500 Rev 11