Brüel & Kjær 3638 Manuel De L'utilisateur page 12

8 Exhaust Noise Inspector Type 3638 – User Manual
Fig.2.4
Wrapping the sound level
meter cable around the
case's foam
5) Insert the foam, with the sound level meter, back into the carrying case.
6) The microphone can now be screwed on to the other end of the extension cable. Fold the
cable and place it and the microphone in their separate compartments as shown in Fig.2.1.
Powering the System
The entire system is powered by a dry lead 6 V/7.2 Ah accumulator (storage battery). Power
consumption is approximately 300 mA at normal operation with up to 3 A peaks during printing.
All necessary power supply plugs are supplied with Type 3638 A/B.
In order to use this common power source with Sound Level Meter Type 2239 A, which does
not have a socket for external power, you must remove Type 2239 A's original backplate and
replace it with a modified backplate available as an optional accessory (see picture of backplate
in Fig.2.5). The modified cover's power supply socket accepts a 1.5 mm angled connector, with
protection against incorrect polarity and high spikes via the battery cover adaptor.
Fig.2.5
Modified back plate for
Sound Level Meter Type
2239 A
When your sound level meter – either Type 2238, which uses a standard power supply plug, or
Type 2239 A – is connected to Type 3638 A/B's battery, it can be switched on via the main
power switch on the controller's front panel. If you want to use the sound level meter as a
stand-alone instrument, unplug it from Type 3638 A/B, insert four standard 1.5 V LR 6/AA-size
alkaline batteries, and in the case of Type 2239 A, use its original backplate. Instructions on the
operation of Type 2238 and Type 2239 A sound level meters as stand-alone instruments require
the relevant Brüel & Kjær user manual.
Caution: The sound level meter batteries must be removed when used with Type 3638 A/B.