BRUEL & KJAER 2305 - Mains Frequency Conversion Procedure

Potentiometer connected the grid of the input tuhe is left open.
Be eareful not to damage the slider and do not bend it, as only a
faultless and properly adjusted slider ensures correct operation.
Changing to Mains Freqnency.
50 Hz (cis) to 60 Hz (cIs) and vice versa.
The two nylon gear wheels accessible through the cover on the right-hand
side of the Recorder (see also Fig. 1.8 on page 14) are replaced by another set
when changing from either of the two frequencies.
50 Hz (cIs) Mains Frequency:
Both wheels should have 22 teeth (Code No. DG 0233).
60 Hz (cIs) Mains Frequency:
The upper wheel (on same spindle as the electromagnetic clutch)
should haye 20 teeth (Code No. DG 0232).
The lower wheel (driving the gear box) should have 24 teeth (Code
No. DG 0234).
Recording of Voltage Levels.
Any voltage leyel between 5 mV (10 mV for DC) and 100 Volts, the frequency
of which is within the range 2-200000 Hz (cIs), or which is DC, maybe re-
corded on the Level Recorder. The Range Potentiometer used on the Recorder
should be chosen according to the expected level variation in the input signal
and the resolution required from the recording. Normally a 50 dB Range
Potentiometer can be used for most types of recording, therefore in the
following the use of this Potentiometer is assumed .
A. GENERAL.
I. Make sure that the Recorder is adjusted for the correct mains voltage,
and then connect it to the power line. Details concerning adjustment to
other mains voltages will be found under "Fuse, Supply Voltage",
page 21.
II. Supply the Recorder with the required type of recording paper and
adjust the writing width accordingly, see also "Insertion of Recording
Paper", page 31 and" Alteration of Writing Width", page 33.
III. Apply th e desired Range Potentiometer (in this case the "50 dB") by
following instruction "Changing Range Potentiometer", page 36.
B.
AC RECORDING.
I. Calibration.
1. Set INPUT ATTENUATOR to "0".
2. Set POTENTIO;\IETER RANGE to "50".
3. Set RECTIFIER RESPONSE to "RMS" .
4 Set LOWER LIMITING FREQUENCY to "20 "
5. Set WHITING SPEED to:
37