Centron Technologies MS930A, Руководство по обслуживанию

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* CAUTION *
Minimum heat dissipation gears to be prepared shall be 100 watts.
Failure to prepare sufficient heatsink for RF board assembly may cause the RF
transistors blown-up.
(4) Set RF power meter, attenuator and spectrum analyzer at proper ranges to check
40.68 MHz power of 150 watts maximum.
(5) Turn on sealer power switch.
(6) Every time when you need to measure any characteristics of RF circuit from
following paragraph (7), push trigger lever at sealing-head or make short-circuit
at control board between P2-pin4 and ground to trigger RF generation.
* CAUTION *
NEVER supply continuous power for more than ten seconds unless sufficient
heatsink is prepared.
(7) Watch power meter and spectrum analyzer. You should have more than 90 watts
when a 50-ohm dummy load is connected at 40.68 MHz.
If you would have no oscillation, turn transformer T1 slowly until oscillation
starts.
Set T1 at mid point of the adjustable ranges where you have oscillation.
(8) Read power meter.
Be sure to read effective power when a sealing gun unit is connected as RF load.
Effective power is calculated as (forward power) - (reverse power).
* NOTE 1 *
Watch the ammeter to read supply current. Normal current will be less than 15A
when a dummy load is connected. When a sealing-head is connected, maximum
current could be as high as 18 amperes.
(9) If RF board would not function properly, really there is not much thing to do.
What you can do on the board is ;
a. Just examine the board by eyes to find any part is burnt or badly soldered.
b. Adjust transformer T1 as para. (7) above to get stable oscillation.
c. Touch to alter shapes of the coil L2 and L4 to change power level a little.
(10) Turn powers off and disconnect test equipment.