Table of Contents
Advertisement
D8125MUX | Operation and Installation Guide | 5.0
5.0 Troubleshooting
Table 17: Troubleshooting
Symptom
Multiplex point appears as
missing at the keypads.
Points intermittently appear
as missing.
One or more multiplex
points remain in trouble or
alarm when all devices
appear normal.
Faulted multiplex points do
not generate alarms or
troubles as programmed.
Control panel transmits PT
BUS TROUBLE reports.
Erroneous alarm or trouble
reports might follow.
Erroneous alarm or trouble
reports appear at keypads.
22
Diagnosis
Multiplex point is not connected
to MUX bus. Check wiring.
Multiplex point not
programmed.
MUX bus wires not connected
to D8125MUX.
Noise problem on MUX bus
loop.
Intermittent shorts or opens on
the MUX bus wires.
The MUX bus is open, shorted
or grounded.
Opens, shorts, or grounds at
various points in the MUX bus
can cause alarms and troubles
depending on multiplex point
programming.
Control panel's reset hook
switch is down when event was
generated.
Two multiplex points are
programmed for the same
address.
Short on D8125MUX, MUX bus
terminals, or short on control
panel Zonex data terminals (25
& 26, 27 & 28).
A multiplex point is
programmed for address 128
or 248 or a D8128D
OctoPOPIT on the same
system has address switches
set for Points 121 through 128
or Points 241 through 248.
Troubleshooting
Remedy
Verify that a multiplex point programmed for the
missing multiplex point is connected to the MUX bus
wiring. Make sure its polarity is correct.
Check the Green Operation LED on the D8125MUX. It
should be flashing. An LED OFF indicates no power, a
D8125MUX PCB failure, or an EEPROM failure on the
D8125MUX.
Verify the missing point's programming with the
Multiplex Point Programmer.
Verify the MUX bus wires are connected to the correct
terminals on the D8125MUX. Verify correct polarity.
Make sure MUX bus wires do not run over fluorescent
lighting or near large AC power transformers or
conduits.
Verify the wiring to the multiplex points and the
D8125MUX does not have nicks or cuts in the
insulation that can short to nearby conduit. Make sure
wires are tight under terminals of multiplex points and
on the D8125MUX.
Remove the sensor wiring from the multiplex point and
meter it for continuity.
There should be no more than 100 of resistance, plus
the EOL resistance. If you read less than the EOL
resistance look for shorts in the wiring.
With the wires for the sensor removed, use a meter to
check them for continuity to ground.
A ground before the EOL resistor on a multiplex points'
sensor loop is interpreted as a short. If the multiplex
point is programmed for trouble on short, a ground
before the EOL causes the multiplex point to send a
trouble report.
The control panel ignores events generated while the
programming or reset switch is down.
Multiplex points programmed for the same address do
not function correctly. Check the programming of each
multiplex point with the multiplex point programmer.
A short on either MUX BUS A or MUX BUS B terminals
generates a PT BUS TROUBLE report. A short on BUS
A or BUS B does not prevent the other from normal
operation. Determine what series of points is wired to
BUS A and BUS B. Check wiring for shorts.
Confirm that a multiplex point is not programmed as
Point 128 or 248. Multiplex points cannot be used as
Points 128 or 248 (these are reserved for control panel
functions). OctoPOPITs cannot be used for Points 121
to 128 or 241 to 248.
Bosch Security Systems, Inc. | 10/09 | F01U034973-02
Advertisement
Table of Contents
