Dynacord DPA 4411 owner manual Battery Operation 24 V DC, Inputs INPUT 1 to INPUT

3.2 Battery Operation 24 V DC

The amplifier DPA 4411 can either be operated on the AC mains or connected to an external 24 V battery power source. Switching to battery operation is accomplished via internal relay.

The battery has to be connected to the corresponding socket (23) on the rear panel of the appliance using insulated AMP flat connectors 6.3x0.8 mm. The amplifier is protected against confusion of poles. Additional internal protection is provided through two miniature fuses – F502 and F503 – one per each conductor (+ and -), which are located on the printed board assembly 85272 (see paragraph 12, diagram 11). For the DPA 4411 the battery cable’s diameter should be at least 2.5 mm2 and the cable length for the single distance should not exceed 4.0 m (max. drop in voltage < 1V).

Caution Operation of the DPA 4411 is solely allowable using batteries without grounding or batteries with grounding of the negative pole. Operation with batteries with grounding of the positive pole is not permissible.

4. Inputs INPUT 1 to INPUT 4

The inputs INPUT 1 to INPUT 4 (15) are electronically balanced. With a sensitivity of 775mV = 0dBu they are meant for the connection of control amplifiers. For the case that floating inputs are needed, the inputs are prepared for retrofitting input transformers.

Note If a switch-contact is located between the control amplifier output and the power amplifier input, switch clicks might become audible during switching. If this is the case, incorporating input transformers (NRS 90208 - one per input) can solve the problem (see paragraph 9.3)

Parallel operation of INPUT 1 to INPUT 4 (15) is possible when using the ROUTING switches (16). This allows to connect the input signal through to feed several power amplifiers with the identical program. Use a permanent marker pen to mark the needed setting of the ROUTING switches (16) next to the ROUTING switch push-button symbol.

diagram 1 input socket connection

diagram 2 LF-cable for coupled operation of two DPA 4411

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