Installation – Johnson Systems EDI-120 Control Retrofit User Manual
Page 5

5
Installation
• Disconnect (turn off) the power supply to the EDI Mark VII dimmer rack(s).
WARNING! Verify all power is disconnected (turned off) before proceeding.
Removal of the old EDI Control Module
• Remove the four (4) mounting screws securing the EDI Mark VII control
module.
• Carefully pull the control module forward until all of the rear wiring
connections are visible. Do not disconnect any wiring at this point.
• If you are not familiar with the EDI Mark VII control module electronics
and wiring, it is strongly advised that you take a few minutes to inspect
the OEM (Original Equipment Manufacturer) wiring (P1 through P6). If
the cables aren’t already labeled, label them using a permanent marker
(Sharpie).
P1 contains the AC power supply conductors (Neutral, Phase A, Phase
B and Phase C) used to power the control module, as well as the low
voltage fan control wiring (positive DC voltage control and common).
Observe the location of the P1 connector and compare it to the location
of the P1 connector on the EDI-120 retrofit. If the P1 connector is
located on the opposite side, refer to the installation of the new EDI-120
retrofit system for details.
On some earlier versions of EDI Mark VII dimmer racks, the fan
control was sensed from the house control inputs, and the fan control
wiring does not come through the P1 connector. If this is the case, the
fan control will need to be rewired from the P1 connector to the fan
SSR. More information regarding this modification is provided in the
“Installation of the new EDI-120 retrofit system” section of this manual.
P2 contains the field wiring connections for DMX and analog control.
NOTE: The P2 connection is obsolete when the EDI-120 retrofit control
module is installed, and all the field wiring must be terminated
on the back of the EDI-120 retrofit control module. Refer to the
installation of the new EDI-120 retrofit system for more details.
P3 contains the PWM output control signals for dimmers 1 through 36.
P4 contains the PWM output control signals for dimmers 25 through 60.
P5 contains the PWM output control signals for dimmers 61 through 96.
P6 contains the PWM output control signals for dimmers 85 through 120.
• All of the internal OEM wiring must remain intact to complete the retrofit.
Compare these connections to the ones on the back of the EDI-120
retrofit control module. Do not disconnect any wiring until you are
completely satisfied with how easy this is going to be.
NOTE: Never pull directly on the wires to remove connectors.