R.V.R. Elettronica VJ3000, Инструкция по установке, техническому обслуживанию и ремонту

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R.V.R. ELETTRONICA S.r.l. (BO) Pag. 79
VJ3000 - Technical and Maintenance Manual
12) Once the output power is at 3 KW, make minor adjustments, using
the
same procedure, to obtain the same power level with a minimum
of anode and grid current. Reduce exciter power if necessary.
5.2 PROTECTION CARD CALIBRATION
Since this card is factory-calibrated, ensure that any adjustment
is actually necessary.
Note: Do not attempt to adjust the position of the temperature
trimmers; calibration is highly complex and should only be performed
at the factory.
To carry out the calibration procedure, it is first necessary to extract
the protection module, unscrewing the 4 rack fixing screws and opening
the top access panel. During this procedure, take care not to undo the
connectors situated on the rear protection module.
Please refer to Table H.
A) ANODE CURRENT PROTECTION ADJUSTMENT (IA)
Perform SETUP 5
1) Connect a dummy load (50 Ohm 3 KW) to the unit.
2) Select ST.BY. (4 Fig.6).
3) Perform SETUP 6 and connect a power supply, set to 0 V across R9,
situated on the power supply module, P1 (6 Fig.7A). The correct
polarity should cause a clockwise meter needle deflection.
4) Increase the power supply voltage and check for a proportional
increase in anode current (on the VJ3000 meter) and in the current
supplied by the power supply.
5) Adjust trimmer R14, situated on protection card, for the right
reading.
6) Adjust the reading (with the power supply) to 1.3A.
7) Using R16 on the protection card, activate the IA protection.
This is confirmed by the lighting of the IA. indicator (19 Fig.5).
8) Reduce the current to 1A.
9) Wait for the protection module to automatically re.enable the unit
and repeat step 6 to check the right threshold (1,3 A).
B) GRID PROTECTION ADJUSTMENT (Ig)
1) Connect a dummy load (50 Ohm 3 KW) to the unit.