MTL MTL4500 Series, Инструкция по эксплуатации

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28
INM4500-2
Mar 2009
6.2.8 MTL4526 - Switch operated relay
Two channel, IS output
The MTL4526 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 fi re 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 certifi ed as non–energy–storing
apparatus, and can be connected to any IS circuit without further certifi cation, provided that
separate IS circuits are such that they would remain safe if connected together.
Figure 6.18
LED indicators
for MTL4526
1 2 3 4 5 6
7 8 9 10 1112 13 14
1 2
1 2
+ – + –
+ –
IS
relay
IS
relay
+ –
*
Vs-
Vs+
20–35
Control 20–35V dc
Contact
inputs
All contacts
shown in
normal position
(relays de-energised)
Loop
powered
* this link appli
only to
contact/logic
operation
Hazardous area
Safe area
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 cve
9 Relay 1 control –ve
10 Relay 2 cve
11 Relay 2 control –ve
13 Supply –ve
14 Supply +ve
PWR
STS
STS
MTL4526
CH2
CH1
Table 6.3
Switch settings
for modes
Mode Function SW1 SW2 SW3 SW4
Contact/Logic
Input
2 ch Off On On On
1in2out On On On On
Loop Powered 2 ch Off Off Off Off