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DIMension 3K
The line, neutral and load connections are made to the
terminal strip mounted on the chassis at the end of the
heat sink. Make sure that the wire gauge used is rated
for the load current. Use COPPER conductors ONLY.
Make sure that all connections are tight and secure.
The terminals should be torqued to 20 in.-lbs. The high
load current can cause
problems if connections
are not properly made.
See the diagram to the
left for the LINE, NEU-
TRAL, and LOAD
connections.
For the most reliable and
stable operation, it is
highly recommended
that each dimmer be fed
from its own breaker in
the distribution panel,
and that SEPARATE
neutrals be run from each
dimmer all the way back
to the distribution panel.
This will help to mini-
mize the possibility of
EMI from the dimmer
affecting other equip-
ment and also EMI from
other equipment affect-
ing the dimmer opera-
tion. Try to keep all the
dimmers on the same
phase and OFF the phase
that is used for the sound
systems for minimum
noise.
Control Circuit Connections
Control wiring is very straightforward and is low voltage
(less than 28 VDC) and low current (less than 50 mA).
Use any type of low voltage hookup wire, but shielded
is recommended for best immunity to possible false
triggering from external interference. Belden 8723
would be a good choice. The HIGH, MID, or LOW
terminal must be momentarily connected to the COM
teminal to select the desired light level. Ususally this is
done by connecting to relays in automation systems.
Alternatively, pushbutton switches could be used for
manual selection of light levels. The relays or switch
contacts must be isolated with no external voltages
applied to them. The application of external voltages to
the dimmer control terminals may result in damage to
the dimmer.
The FULL terminal is used to place the dimmer instantly
in the full brightness mode. This is useful for emergency
situations such as a fire alarm. This terminal requires a
latching connection to the COM terminal. As long as the
connection is closed between the FULL and COM
terminals, the lights will stay at full brightness regardless
of the condition of the other terminals.
Adjustment
The dimmer has three light levels which must be adjusted
for each individual theatre. The DIM 3k has a removable
jumper called FADE which can be easily removed to
make the adjustment process quick and easy. This jumper
is located close to the three trimpots which are used to set
the light levels. When the jumper is removed, the light
level changes instantly as you
adjust the trimpots so you do not
have to wait and wait for the light
level to stabilize each time you
turn the trimpot. When you are
finished making the adjustments
for each of the three light levels,
replace the jumper so that light
level changes are smooth and
gradual for normal operation.
OPERATION
There are no usual operation requirements since in most
cinemas, the dimmers are comtrolled by the automation
system. The only operator accesible controls are the
manual override pushbuttons on the wall mount unit. If
the installer has installed some other type of manual
control, please refer to the instructions given by the
installer or cinema manager on the proper operation.
Usually the only time that requires operator intervention
is if the automation system has failed and the booth is
being run manually. Pressing the appropriate pushbutton
will select the desired light level.
Light Level Adjustment Trimpots
Fade Jumper