Digital fire detection control panel
LYON
FIRE PROTECTION MANUFACTURER
Ctra. de Molins de Rei a Rubí, Km. 8,4 - 08191 RUBÍ (Barcelona) ESPAÑA.
Tlf.: +34 935 862 690 - Fax:+34 936 999 261 - [email protected] -
www.cofem.com
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RELAY SHORT CIRCUIT 01
(Short circuit for the relay 1 of the MDA1Y, MDA2Y or MYOA)
Cause
There is a short circuit between the output of the relay 1 of the MDA1Y, MDA2Y or
MYOA and the end-of-line resistance.
Solution
Check that the MDA1Y, MDA2Y or MYOA is correctly connected to the sounders
connected to it, check that the 33 K
end-of-line resistance and the supervision diodes are
correctly mounted (see chapters 1.5.3.2, 1.5.3.3 and 1.5.3.7). To operate correctly, the
output voltage of the relay 1 of the MDA1Y, MDA2Y or MYOA should be between -2 V
and -7,8 V in standby and 24 V to 29 V when activated.
RELAY OPEN CIRCUIT 02
(Open circuit for the relay 2 of the MDA2Y)
Cause
There is a lack of continuity between the output of the relay 1 of the MDA2Y and the end-
of-line resistance.
Solution
Check that the MDA2Y is correctly connected to the sounders connected to it, check that
the 33 K
end-of-line resistance and the supervision diodes are correctly mounted (see
chapter 1.5.3.2). Check the status of the fuse protecting the module. To operate correctly,
the output voltage of the relay 2 of the MDA2Y must be between -2 V and -7,8 V when in
standby and between 24 V and 29 V when activated.
RELAY SHORT CIRCUIT 02
(Short circuit for the relay 2 of the MDA2Y)
Cause
There is a short circuit between the output of the relay 2 of the MDA2Y and the end-of-
line resistance.
Solution
Check that the MDA2Y is correctly connected to the sounders connected to it, check that
the 33 K
end-of-line resistance and the supervision diodes are correctly mounted (see
chapter 1.5.3.2). To operate correctly, the output voltage of the relay 2 of the MDA2Y
must be between -2 V and -7,8 V when in standby and between 24 V and 29 V when
activated.
24V RELAY
( 24V Fault in module MDA1Y, MDA2Y or MYOA)
Cause
The 24 V voltage does not reach the module from the power supply’s 30 V output, which
may be from the control panel or from an auxiliary external power source.
Solution
Check the connections for the 30 V line from the control panel’s power source, or
auxiliary external power source, to the 24 V input to the MDA1Y, MDA2Y or MYOA
module, (see chapters 1.5.3.2, 1.5.3.3 and 1.5.3.3). To operate correctly, the 24 V voltage
input to the modules should be between 20 V and 29 V.
OC INPUT 01
(Open line in MSTAY input 1)
Cause
There is a lack of continuity between the input of the relay 1 of the MSTAY and the end-
of-line resistance.
Solution
Check the correct connection of the MSTAY elements connected to it, verify the correct
assembly of the end of line resistor, 33 K
(see chapter 1.5.3.4.). The MSTAY voltage
input 1 for proper operation should be between -5 V and -7 V at rest.
SC INPUT 01
(Short circuit in MSTAY input 1)
Cause
There is a short circuit between MSTAY input 1 and the end of line resistor.
Solution
Check the correct connection of the MSTAY elements connected to it, verify the correct
assembly of the end of line resistor, 33 K
(see chapter 1.5.3.4.). The MSTAY voltage
input 1 for proper operation should be between -5 V and -7 V at rest.
OC INPUT 02
(Open line in MSTAY or MYOA input 2)
Cause
There is a lack of continuity between the input 2 of the MSTAY or MYOA and the end-
of-line resistance.
Solution
Check the correct connection of the MSTAY elements connected to it, verify the correct
assembly of the end of line resistor, 33 K
(see chapter 1.5.3.4 and 1.5.3.7). The MSTAY
and MYOA voltage input 2 for proper operation should be between -5 V and -7 V at
rest.
