UPGRADE (June 2003):
INSTALLING AUXILIARY POWER TRANSFORMER FOR MANLEY MIC/EQ 500

PURPOSE: To up-rate the amperage capability of the heater supply.  

METHOD: To install a separate dedicated transformer for the heater circuit.

UNITS AFFECTED: Serial numbers for units that will benefit from this update are

MPE5000 (10/1996) through MPE5057 (11/2001).

UPDATE KIT INCLUDES:

a)       ONE MCI 2-30-2298 16VAC 2A POWER TRANSFORMER FOR HEATERS

b)        Four screws

c)        Mounting bracket for transformer

d)        Shrink tubing and solder

e)       Instructions and drawings for procedure

TOOLS REQUIRED:

a)       Phillips #1 screwdriver

b)       Wire strippers 

c)        Soldering Iron

PROCEDURE FOR INSTALLING AUXILIARY POWER TRANSFORMER ON 
MANLEY MIC/EQ 500

1. Disconnect AC power from unit. 
You will be working with the mains connections so it is imperative that you UNPLUG the unit from the wall.

2. Remove silver 4-40 x 1/4" flathead screws securing both top and bottom covers using a phillips screwdriver and slide covers off towards the rear of the unit. Put covers aside.

3. Insert the wires from the new transformer through the vent slots on

the back panel as shown below. Be careful not to damage the insulation. 

4. Remove the four phillips head screws that mount the existing power transformer. Using the new

longer screws we supplied you, install the new transformer and mounting bracket through these same holes as shown below. 

5. Looking at the underside of the unit, there are three pairs of wires that run

from the existing power transformer to the circuit board. Disconnect the center

pair from the circuit board, and also disconnect them from the existing

transformer (these are the windings labeled 0-15v on the old power transformer). 
We will be using the new transformer instead of the old transformer to supply voltage to this part of the circuit.

So remove these two old wires from the old transformer and discard them.

6. Attach the two red wires from the new transformer to the circuit board to the place on the circuit board where the old wires were connected as shown above. It doesn't matter which one goes in which position.

7. Turn the unit over top side up, and attach the green wire from the new transformer to the

center (ground) terminal of the ac power connector as shown below. 

8. The new transformer has two primary windings which can be wired in parallel for 120v operation or wired in series for 230v operation. 

Newest MCI 2-30-2298 (2005 instructions)
For 120v operation, connect the black and blue wires together, and connect the brown and white wires together.  Connect the black and blue wires to the side terminal on the fuseholder, then connect the brown and white wires to the upper left (0v) terminal of the power transformer at the side pin, 2nd from the top.
For 230v operation, Connect the brown and black wires together and insulate them off together with heat shrink tubing. Tuck these away. Connect the blue wire to the side terminal of the fuseholder as shown below. Then connect the white wire to the upper left (0v) terminal of the power transformer, 2nd pin from the top as shown below.

Connect the transformer's Green/White shield wire to the 3rd pin mains GROUND lug.

9. Secure all wires with cable ties, insuring that no wires are in contact with any sharp corners. 
Re-connect AC power and check for proper operation. 
You should be able to measure around 16 Volts AC across the two red wires going to the printed circuit board.

That’s it! No further adjustments or calibrations are necessary.

For further info or to order this kit, please contact our service department.
If you would like to send your unit in and have Paul perform this upgrade for you, please contact him at the address below:

Location of this page online: 

http://www.manleylabs.com/techpage/MICEQ500XFMR2.html