User manual

MIDI KEYBOARD CMK-2 INSTALLATION MANUAL v1.5

CMK-2 Manual 1.5.doc 2009 CLASSIC ORGAN WORKS 13

Power Connections

If you are using multiple keyboards, connect the red and black wires as illustrated in the diagram below (to parallel the

boards) and then connect the supplied DC power supply to the co-axial power connector on one board. The power

supply can be plugged into any one of the manuals. Make sure that you use red wires for the +12V (A terminals) and

black wires for the Ground (B terminals).

If you have a stack of four keyboards, you may use one power supply of 1 Amp capacity or two of 500 mA. If the

latter, parallel only two keyboards per power supply.

When the keyboard is powered and operating, the green ‘Heartbeat’ LED between the MIDI IN and MIDI OUT

connectors will be flashing.

DC 12V

POWE

TERMINAL

BLOCK

AABB

DC POWER

SUPPLY

Figure 7: Power Terminal Block Connections

Additional Information:

• If the CMK-2 is to be mounted in an existing organ, it can be connected to the organ power supply. See

Figure-33 in Appendix-C for details.

• The CMK-2 has a bridge-rectifier, and can accept power supplies with either positive or negative on the centre

pin of the 2.1mm (0.080") Co-axial Power Jack.

• The CMK-2 requires between +9V and +15V DC at a minimum current of 120 mA per board. The supplied

power supply (500 mA) is good for up to three keyboards. One with more current capability (typically 1 Amp)

should be used for four keyboards, or else use two smaller power supplies for two keyboards each.

• A 500mA self-resetting Polyfuse on each board provides over-current protection.