Alignments - QUANTACHROME INSTRUMENTS MULTIPYCNOMETER Manual

5.3.2.2. DC POWER -ON CHECKS
5.2.2.1. REMOVE THE PRESSURE TRANSDUCER CONNECTOR FROM THE SMALL
PRINTED CIRCUIT BOARD (PART NUMBER 00003) LOCATED INSIDE ON THE
LEFT BULKHEAD.
5.2.2.2. CONNECT THE INSTRUMENT TO THE 120 VAC SUPPLY OUTLET (OR TO
THE CUSTOMER REQUIRED VOLTAGE) AND TURN THE POWER SWITCH TO THE
"ON" POSITION.
5.2.2.3. USING A CALIBRATED DIGITAL VOLT METER, CHECK AND ADJUST THE
POWER SUPPLY FOR DC OUTPUT VOLTAGE SUPPLIED TO THE CIRCUIT CARD.
THE READINGS ARE TAKEN AT THE POWER SUPPLY TERMINALS AND ARE
REFERENCED TO THE NEUTRAL POST. THESE READINGS SHOULD BE +24.00 
0.01VDC AT THE POST RED & YELLOW AND + 5.00  0.01VDC AT THE POST
COM. & ORG.
5.2.2.4. CONNECT THE VOLTMETER LEADS TO THE PRESSURE TRANSDUCER
PLUG ON THE SMALL PRINTED CIRCUIT BOARD AND VERIFY THAT +24 
0.01VDC ARE MEASURED ACROSS PINS 4 AND 6.
5.2.2.5. TURN THE POWER SWITCH TO OFF AND THEN RECONNECT THE
PRESSURE TRANSDUCER CONNECTOR TO THE SMALL PRINTED CIRCUIT
BOARD.
5.3.

ALIGNMENTS

5.3.1. DIGITAL PANEL METER
5.3.1.1. TURN THE INSTRUMENT'S POWER SWITCH TO ON. VERIFY THAT THE
DIGITAL PANEL DISPLAYS NUMBERS THAT ARE BRIGHT AND CLEAR.
5.3.1.2. TURN THE ZERO ADJUSTMENT KNOB ON THE FRONT PANEL FROM
STOP TO STOP SLOWLY AND VERIFY THAT SMOOTH DIGITAL CHANGES OCCUR
AND THAT ALL SEGMENTS OF EACH DIGIT ILLUMINATE.
5.3.1.3. TURN THE ZERO ADJUSTMENT KNOB ON THE FRONT PANEL TO THE
MID-RANGE POSITION (5 TURNS FROM THE STOP FOR A TYPICAL 10 TURN
POTENTIOMETER).
5.3.1.4. TURN THE SELECTOR VALVE TO THE CELL POSITION AND OPEN THE
GAS OUT TOGGLE VALVE TO VENT THE CELL. AFTER 5 MINUTES OF WARM UP
TIME ADJUST RESISTOR R1 LOCATED ON THE SMALL PRINTED CIRCUIT
BOARD FOR A READING OF 0.000 PSIG ON THE DIGITAL PANEL METER. THIS IS
PERFORMED BY PLACING A JEWELER'S SCREWDRIVER THROUGH THE HOLE IN
THE BACK PANEL AND TURNING THE POTENTIOMETER UNTIL THE DIGITAL
PANEL METER READING DISPLAYS 0.000 PSIG.
5.3.1.5. PLACE A SMALL AMOUNT OF TORQUE SEAL BETWEEN THE
ADJUSTMENT KNOB AND THE BODY OF THE POTENTIOMETER R1 TO INSURE
THAT IT REMAINS UNCHANGED DURING SHIPMENT.
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