Instruction manual

Operation
22 025-9209
Radio System
A radio stuck in transmit for any reason (PTT held in,
electronic failure, chattering PTT, etc.) will prevent or
interfere with other transmissions. Radios should provide a
PTT timer that prevents continuous transmission for
extended periods, usually three minutes. This only helps if
the radios are functioning properly. It will not prevent all
cases of transmit lock-out.
RS-232
Transmit or receive data failure will cause loss of
communications between the PC and the Controller. This
will cause communications failure states at all RTUs and the
Controller.
Buffering
If communications fail, the Controller will buffer 200 bytes,
a minimum of 10 messages. After the buffer is full, the
controller will stop acknowledging the RTUs and a critical
system communications fail status will occur.
Ground
Poor grounding or no common signal ground can cause
intermittent communications. A power cycle may appear to
cure this situation for short periods of time.
Critical System Failures Summary
Critical system failures can be caused by any of the following conditions:
Chattering input causing repeated transmissions
Radio stuck in transmit due to:
¾ PTT held on by RTU, user, or radio failure with no timeout
¾ Radio locked in transmit due to radio failure
¾ Carrier from another radio system causing interference
¾ Hardware/firmware failure causing chattering PTT
Repeater down
Controller radio down with no standby or backup
Controller is down due to:
¾ COR stuck active
¾ Power failure
¾ Equipment failure
¾ Hardware/firmware failure causing chattering PTT
RS-232 connection to Controller is down
PC or software failure