SC4x0 Technical manual
Page 19 of 34
SeaCom
Rev
2.00
8.2 Example of a simple set up with handset
This example shows how to connect supply & handset to the telephone.
8.3 Example of set up with remote PTT for loudhailer
This example shows how to connect loudhailer in remote location
8.4 Ground & shield connections
It is very important to connect or terminate all shields correct. Normally shields should be terminated to
ground or ship hull in both ends and not carry any signal (forward or return). Due to possible high
ground currents in case of earth leakage or lower shield resistance, it recommended to terminate in
one end only.
In general, power and line should be terminated at the exchange and remaining wires at the
telephone.
It is very important to connect ‘PE’ to ground or ship’s hull for protection and to avoided noise
interference. Connection between ‘PE’ and ground should be as short as possible.
PE
Handset SP
Hook Sw. signal
Handset Mic
SC410/420
+24V
0V
Relay COM
Relay NO (or NC)
PE
T1A
T2A
PE
NOTE: If shield is connected at
APBX do NOT connect to PE at
telephone end
Always only connect one end due
to possibly high ground current
when
used off shore
To bell or alarm relay coil
NOTE: If connected to DC
coil –use protection diode.
Hook Sw. 0V
Cradle switch must be potential
free.
Switch must close when handset is
off hook.
Cradle Switch is connected to Hook
Sw. on telephone
If cradle have a double switch, use
the other for connecting speaker.
PE
Handset SP
Hook Sw. signal
Handset Mic
SC410/420
+24V
0V
Relay COM
Relay NO (or NC)
PE
T1A
T2A
PE
NOTE: If shield is connected at
APBX do NOT connect to PE at
telephone end
Always only connect one end due
to possibly high ground current
when
used off shore
To bell or alarm relay coil
NOTE: If connected to DC
coil –use protection diode.
Hook Sw. 0V
Cradle switch must be potential
free.
Switch must close when handset is
off hook.
Cradle Switch is connected to Hook
Sw. on telephone
If cradle have a double switch, use
the other for connecting speaker.
PE
Headset PTT
Ext. Speaker
Headset PTT function needs to
be assigned to loudhailer PTT
from the menu system.
NOTE: When using headset
PTT for remote loudhailer,
due to noise picked up by the
cable, adding a slave relay
located next to the telephone
may prove beneficial.
Line
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