ETC Matrix MkII Dimming System - Manual (Page 42)

Table of Contents 37
Failure of group of dimmers
An assessment of the number of dimmers affected is crucial for effective corrective
action. This will determine whether the problem is a mains supply problem, a dimmer
rack problem or a control problem.
Check the Processor front panel display for the presence of all phases of the mains
supply. If the mains supply is not present, check fuses or MCBs which power the
processor and Chassis. Before resetting the main supply, investigate and correct the
cause of the failure.
If the mains is present, and no control signal bar graphs are showing, check that the
control signal input connector is in place.
The dimmer operation can also be checked by using the manual preset control
feature in the PRESETS menu.
Check if the failure is restricted to a column or row in the Matrix Chassis. If it is a
column, it could be due to a phase failure and if a row, the DMX connection may be
missing. DMX is looped from one row to the next, so a group of rows without DMX
could indicate a faulty or disconnected DMX cable in the row above the fault.
Failure of single dimmer
The fault reports through DimSTAT will give details of a circuit fault and if the fault
cannot be repaired externally, the problem may be a single dimmer failure. In the first
instance disconnect all loads and extension cables from the connected sockets and
check the dimmer channel again. If the problem still exists, the module concerned
should be replaced.
Over temperature alarm
If modules or dimmer racks report high temperatures, this may be due to either a
reduction in the efficiency of the ventilation system (caused by a fan failure) or the
effect of an unusual load. Check the load in the first instance, and also the
temperatures of adjacent devices.
Over voltage alarm
The dimmers affected by either an over or under-voltage condition will report the
problem and will then shut down until the voltage returns to the specified range. This
is to protect the loads from high voltages which would affect the life of the lamps
connected. Check that the default voltage calibration settings are correct. If these are
too low, a small variation in nominal voltage may cause nuisance reports and dimmer
switch off.
Serial data loss
If DimSTAT loses communication to the dimmers, the first step is to check the
mechanical connections to the network. If this is intact, reboot the PC and check
communications and the comms port settings, in case the settings have been
corrupted by additional software loaded on the hard disk .
DMX data loss
The Matrix dimmer has a backup scheme for DMX whereby the response to a failure
of DMX can be set to hold the last valid DMX state, fade to blackout, or go to a preset
state.
If there is a partial DMX loss, it may be caused by a dimmer rack being removed and
breaking the link from one rack to the next, or that the DMX cables have been
connected incorrectly when a dimmer rack is replaced.