Bell
Technical Support
System
Tel 0845 121 4008
(Telephones) Ltd
Fax 0845 121 4009
Web
www.bellsystem.co.uk
Telephone Ring Problems
Phone doesn’t ring
1. Broken wire between the call button for that flat
and the phone (Terminal I). Try a spare core.
2. Broken wire between the phone (Terminal O) and
the speech unit. Check if the lock button or
speech work, if either does then the O connection
is ok.
3. No voltage getting through to I and O terminals
on the phone. Check at least 10V across I and O
when the call button is pressed or shorted.
4. Dodgy call button. Short the 2 terminals to prove.
5. Missing connection between C on the speech unit
and the call buttons (no phones ring).
Phone ring’s but not
heard at the entrance
1. Missing ‘R’ or shorted connection between phone
and speech unit. There will also be no speech
heard at the entrance.
BS-LX phone flashes red
and green periodically
instead of ringing
1. No 12V DC to connection ‘V’, check at least 8V
between V and O on the phone when it is ringing
(highest current). Also check there is power at the
phone by pressing the bell button on the phone
and seeing the mute light come on.
Mute LED won’t light on
a phone.
(not all models)
1. No 12V DC on terminal ‘V’.
Door open LED does not
come on, on the phone
(not all models)
1. No 12V DC on terminal ‘V’
2. ‘L’ terminal no shorting to 0V when the door is
open. Connect L to O on the phone to check
phone.
