DH Instruments MOLSTIC-S, Руководство по эксплуатации и обслуживанию

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MOLSTIC-S™ OPERATION AND MAINTENANCE MANUAL
© 2004-2007 DH Instruments, a Fluke Company
Page
30
Slowly raise system pressure to desired test pressure: Rotating the regulator’s
control knob clockwise raises the outlet pressure. Rotate counterclockwise to lower the
outlet pressure. Increase the system pressure to the desired DUT operating pressure.
Make final adjustments of control pressure in the direction of increasing pressure in order
to obtain the most accurate and stable set point. Provide additional margin in the control
pressure only if the final pressure will be within the safe operating range of the molbox.
3.1.2 REGULATOR MAXIMUM PRESSURE ADJUSTMENT
Once the regulator has been adjusted to the desired pressure its adjusting stem should be
locked down to prevent further adjustments. This will help protect the molbox RPTs from
over-pressurization.
Remove regulator knob cover: Use a small flat screwdriver to remove the plastic cap
on the top of the regulator adjustment knob.
Loosen jamb nut: Using the properly sized socket wrench, loosen the jamb nut located
on top of the adjustment knob.
Adjust knob position: Rotate the regulator adjustment knob clockwise until it gently
bottoms out against the regulator body.
Tighten jamb nut: Hold the adjustment knob in position while using the socket wrench
to tighten the jamb nut against the top of the adjustment knob.
Retest system pressure: Vent the system pressure. Use the procedure in Section 3.1
to re-pressurize and verify the regulator pressure setting. Readjust if necessary.
Replace regulator knob cover: Place the regulator adjustment knob cover back on top
of the knob and gently snap back in place.
3.1.3 PRESSURE REDUCING REGULATOR ADJUSTMENT
During operation, the pressure reducing regulator can be finely adjusted to control or limit
molbloc-S flow and operating pressure by rotating the regulator adjustment knob. (See
Section 3.4)
3.2 SYSTEM PRESSURIZATION AND REGULATOR
ADJUSTMENT – BACK PRESSURE REGULATOR
During system operation, be extremely careful not to apply pressure in excess of the maximum
operating pressure of the molbox: 600 kPaa (87 psia) for molbox1-A700K; 250 kPaa (36 psia) for
molbox1-A350K.
Once the test system with molbloc-S and molstic-S has been completely interconnected, the following procedure
should be used for its safe pressurization and operation.
The pressure directly upstream of a back pressure regulator is controlled by adjusting the position of the control knob.
Rotating the knob in the clockwise direction raises the upstream (control) pressure. Counterclockwise rotation,
coupled with venting of the downstream side of the regulator plumbing, lowers the upstream pressure. molstic-S
regulators are NOT self-venting therefore the upstream pressure will not be adjusted with rotation of the control knob
unless the downstream gas is allowed to escape.
Make final adjustments of control pressure in the direction of increasing pressure in order to obtain the most accurate
and stable set point.