Fault Diagnostics
21
Revision 1.0 - 7-May-02
HUB24 Series Dimmer
Operating Manual
5.1.3
Thermal protection
The HUB24 dimmers primarily use convection cooling, so reducing the air flow to
the unit can produce over-heating. The temperature of each of the heatsinks are
individually monitored.
If the temperature of a heatsink gets close to maximum the fan on that heatsink will
be turned on and a “Fan Activated” warning message is displayed (also placed in the
error log). Press either button to acknowledge the warning and restore the display to
normal.
If the temperature of a heatsink rises above maximum, all three dimmer channels on
that heatsink will be will be shutdown. No indication of this shutdown is displayed.
The channels will be restored when the heatsink temperature returns to a lower level.
5.1.4
Neutral – Earth voltage
The HUB24 will detect voltage problems generated by a poor or missing neutral
connection. A poor (resistive) neutral connection can cause arcing and overheating of
the connector and also allows the phase-to-neutral voltages to vary, causing
overvoltage damage to components.
Bad neutral connections account for many lamp and dimmer failures. While the
internal electronics of HUB dimmers can tolerate these fault conditions, other
equipment run from the same mains supply generally cannot.
If the voltage between the neutral and earth exceeds the allowed maximum, all the
dimmer outputs are turned OFF and a “Neutral Earth Fault” warning message is
displayed (also placed in the error log). When the neutral-earth voltage condition is
removed, press either button to reactivate the dimmer outputs. The outputs will
restart according to the previous settings.
Neutral-earth voltages are most commonly caused by poor (resistive) neutral
connections or undersized neutral wires in supply cables. Screw terminals in
connectors can loosen with use and these should also be checked if this fault occurs.
The Neutral-earth fault detection can be disabled using the Fault Detect menu item
(see section 4.2.17).
5.2
Output faults
If a short-circuit lamp or output cable is plugged into a dimmer output, the circuit
breaker will disconnect the fault from the dimmer. In nearly all circumstances, it is
quick enough to prevent damage to the output devices.
If an output device does fail the symptoms will be the dimmer output at a fixed level
(off, half or full) regardless of the control level. If a fault does occur, that channel may
be isolated with its circuit breaker.
Note: If a channel is not responding to DMX control, ensure it is not being controlled
by playback or test (see 4.2.24) before suspecting an output device has failed.
5.3
Software exception errors
If a message appears on the display like “ADR ERROR EXCEPTION XXXXXXXX
XXXXXXXX” where the Xs represent different characters, write down the complete
message and contact JANDS Service Department or your local JANDS Distributor,
giving details of the dimmer’s operating conditions that caused the error. Press either
button to restart the dimmer, if the error prevents normal operation a Deep Clear will be
required (see section 4.3).
