QSC Audio DDI-11 manual Introduction, II. Alternate Uses, Inputs, ON/OFF Control, Power Supply

Instructions for the DDI-11 DataPort Accessory Card

I. INTRODUCTION

The DDI-11 DataPort Accessory Card is designed for use with QSC amplifiers equipped with a DataPort connector. It provide an easy way to exploit the features of the DataPort without using QSControl or an accessory.

Through a terminal block with eight screw clamps on the DDI-11, the DataPort offers these connections:

•Balanced input to Channel 1.

•Balanced input to Channel 2.

•Analog (signal) ground.

AUDIOQSC ©2004

J1

VM1

IM1

PROT

IM2

VM2

J2

300mA

+15V

CGND

STBY

IN 2+

IN 2-

AGND

IN 1-

IN 1+

•Chassis ground.

•Standby control; connecting this terminal to chassis ground shuts off the power supply, except on ISA Series amplifiers.

•+15 volts (at up to 300 mA), except on ISA and the original PowerLight Series* amplifiers.

Figure 1. The DDI-11 and its control/monitoring connections.

The screw clamp terminals can accept stranded wire as large as 17 AWG (1 mm2) or solid wire as large as 16 AWG (1.5 mm2).

The DDI-11 card mounts onto the DataPort connector on the back of the amplifier and secures to the amplifier with two screws. A small sheet of insulative fish paper protects the underside of the card.

To guard against oxidation, corrosion, or contamination, the circuit board is treated with non-toxic protectants. Therefore, it may have a slight odor and a slightly oily-feeling residue. Do not wash the protectant off the circuit board.

INPUTS

Each channel of the amplifier has a balanced input connection on the terminal block (see Figure 2). Each input comprises two terminals, + (in polarity) and - (out of polarity). For optimum immunity to noise, use a balanced connection whenever it is possible.

		+15V (ref: CGND) supply
300mA		Chassis Ground
	+15V
	CGND	Power Suppy Standby
	STBY
		- }
	IN 2+
		+	Channel 2 Balanced Input
	IN 2-
	AGND	Analog (Signal) Ground
	IN 1-
	IN 1+	+- } Channel 1 Balanced Input

Figure 2. Eight screw clamp terminals offer connections for inputs, remote on/off control, and a 15-volt DC supply.

For an unbalanced connection, connect the signal conductor of the

cable to the + input and the shield to the - input; also, connect a short jumper wire between the - input and the analog ground terminal.

With the amplifier channel at full gain, the input sensitivity (for 8-ohm loads) of the DataPort input is approximately 3 volts rms (+11.8 dBu).

ON/OFF CONTROL

A switch closure between the chassis ground and the standby terminals will put the amplifier’s power supply in standby. Opening the closure will restart the power supply, with no inrush current surge. The standby terminal is isolated through a diode, so you can gang together any number of amplifiers equipped with DDI-11 cards to be controlled by a single switch closure. ISA Series amplifiers, however, do not have this feature.

POWER SUPPLY

The +15 volt output is referenced to the chassis ground terminal and will provide up to 300 mA to power custom accessories or other devices. The output is protected from short circuits or excessive current draw by a self-resetting polyswitch fuse.

The +15 volt terminal on ISA and original PowerLight Series* amplifiers, however, cannot provide enough current to power external circuitry. Doing so may collapse an ISA amplifier’s internal low-level supply rails or burn out a series resistor on the input board of an original PowerLight amplifier.

II. ALTERNATE USES

The DDI-11 may also be used to connect to any DataPort connector on QSControl MultiSignal Processors and Basis products. Used this way, the DDI-11’s four signal input terminals now become signal outputs, allowing you to use the audio signals for whatever purpose you require. The standby and power supply terminals cannot be used in this application.

*The original PowerLight Series comprises the models PL 1.0, PL 1.0HV, PL 1.4, PL 1.5X, PL 1.6HVX, PL 1.8, PL 2.0HV, PL 2.4MB, PL 3.4, PL 4.0, PL 6.0PFC, PL 6.0 II, and PL 9.0PFC. It does not include the PowerLight 2 Series, which can be used to provide accessory power.

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