Operation; General Arrangement; Maintenance - MEDC DB4 Technisches Handbuch

3.0 OPERATION

The operating voltage of the unit is stated on the unit label. The speaker is available in 4 standard wattage ratings
from 8 watts to 25 watts and in Exd or Exde versions. Different sound levels can be obtained by selecting the
transformer tappings in the unit. See table below for details.
Alternatively if requested when ordered, the unit can be supplied with a direct 8Ohm connection to the driver for
connecting to a suitable audio source.

4.0 MAINTENANCE

During the working life of the unit, it should require little or no maintenance. GRP will resist attack by most acids,
alkalis and chemicals and is as resistant to concentrated acids and alkalis as most metal products.
However, if abnormal or unusual environmental conditions occur due to plant damage or accident etc., then visual
inspection is recommended.
If the unit requires cleaning, then only clean exterior with a damp cloth to avoid electro-static charge build up.
Repairs should be undertaken by returning the unit to MEDC or by an authorised repairer of Ex equipment.
If a unit fault should occur, then the unit can be repaired by MEDC. All parts of the unit are replaceable.
If you acquired a significant quantity of units, then it is recommended that spares are also made available. Please
discuss your requirements with the Technical Sales Engineers at MEDC.
10/11
Transformer
Tappings
25W
1:2 25.0
2:3 12.5
3:4 6.0
1:3 4.0
2:4 2.0
1:4 1.0

GENERAL ARRANGEMENT

Power (W)
20W 15W 8W
20.0 15.0 8.0
10.0 7.5 4.0
6.0 5.0 2.0
5.0 4.0 1.5
2.0 2.0 0.7
1.5 0.8 0.4
© Cooper MEDC 2011