Installation Sheet
RDM-3FDB Triple Channel Lutron FDB Ballast Dimmer
1900 W
The RDM-3FDB Triple Channel Ballast Dimmer is a 1920 W positive air gap
relay and dimmer, built for strength and for reliable switching/dimming of
Lutron FDB ballasts. It is designed for use with the RDA series of enclo-
sures, in an AMX Lighting™ modular digital dimming system. The RDM-
3FDB module's 120, 240, and 277 VAC ratings are CE, UL, and C-UL
approved.
RDM-3FDB UL and C-UL Ratings
• 120 VAC, 1920 W
• 240/277 VAC, 1920 W
Suggested Dimmed Loads
• Most 3-wire dimmable fluorescent ballasts
• Lutron© Hi-Lume® FDB Ballasts
• Lutron Eco-10® Dimmable Ballasts
Specifications
• Dimensions (HW): 10.0" x 2.75" (25.4 cm x 6.99 cm)
• Dimmed output protected by a 250 mA GMA 5 x 20 mm fuse
• Phase dependant
• Use wires rated at 75°C (167°F)
• Torque terminals to 20 in-lbs. (2.3 N/M)
• Max. wire size: 10 AWG (4 mm²)
• Weight: 1.57 lbs. (0.712 kg)
•BTU/hr: 5
• Control current: 85 mA @ 12 VDC
• For use with FDB ballasts
Caution: Pre-Installation Notes
• All Class 1 wiring must be connected to proper terminals.
• All control wiring must be connected to proper terminals.
• Disconnect power while installing or connecting the unit.
• Keep top and bottom air vents clear at all times.
• Use field installed copper conductors.
• All electrical ratings are for continuous duty.
• For indoor use only.
• This module may require extra power from the AXlink connection or an
external power supply connected to the control card.
Connecting the RDM-3FDB to the AMX Lighting Master
Lighting Application Drawing
FIG. 1 RDM-3FDB
Relay
Line in (hot)
Switched out
Dimmed out
Fuse
Positive air
gap relay
Relay
Line in (hot)
Switched out
Dimmed out
Low-voltage control wiring:
4-pin connector to AMX
Lighting master controller
Mounting
points
Ballast A
Ballast B
Relay
Line in (hot)
Switched out
Dimmed out
Ballast C
FIG. 2 RDM-3FDB connections
FIG. 3 RDM-3FDB wiring configuration
Pin 3 (RLY)
Pin 2 (DIM)
Pin 1 (+12 V)
RDM-3FDB 4-pin module connector
3 (-)
2 (AC)
1 (+)
4-pin plug from RDM series module
Note: The 4-pin plugs from the module connector
to the 4-pin connector on the master (black plug cover facing up).
BALLAST
Ballast
Circuit breaker
panel
Line in (HOT) Switched
Dimmed
Florescent
Ballast
Neutral
Neutral
All neutrals are
common to the
Neutral block in the
enclosure. Provide a
separate neutral for
each load.
The fuses protect the dimming
circuit from a low impedance
load.
• The fuse would blow if it
were incorrectly wired
• Catastrophic ballast failure
• Reversing switched and
dimmed circuits
• Reversing dimmed and
line circuits.
The dimmed output must be
connected to a high impedance
load.