Fluke PG9000 Series, Руководство по эксплуатации и обслуживанию

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PG9602™ OPERATION AND MAINTENANCE MANUAL
© 2011 Fluke Calibration Page
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gg.gg is made up of mass from the gram trim mass set (masses of 50 g to 0.01 g). These masses
can be loaded in any order.

Caution
When PG9000 provides mass loading instructions and calculates the actual true
mass of the requested load, it assumes that the mass set in use has been set up
correctly (see Section 2.3.1.3). For PG9000 mass loading protocol to operate
properly, the mass set in use must be EXACTLY the mass set that has been
defined by the add and/or edit mass function (see Section 3.12.1.6).
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Mass loading instruction using PG9602 and MS-7002-80 (80 kg) mass set:
EXAMPLE: Manual Mass Loading when using the low range 10 kPa/kg piston-cylinder:
47.9 kg and 10.45 g
Load:

piston (0.5 kg)

bell (0.8 kg)

9 kg #1 (makeup mass)

10 kg #1 through #3

5 kg #1

2 kg #1

0.5 kg #1

0.1 kg #1

10.45 g from trim mass set
3.7 AMH Mass Loading
3.7.1 Operating Principals
Note
Numerical reference in this section refers to Figure 15.
The purpose of the AMH system is to automatically load specified values of mass onto the
PG9000 piston-cylinder. This is accomplished by a three step process of, 1) lifting the
complete mass set up, off, and above the piston-cylinder to the mass selection position, 2)
selecting the individual masses to be loaded and retained, and then, 3) placing the masses to
be loaded back onto the piston. It uses pneumatic drive pressure to lift the mass stack and to
actuate the binary mass retaining pins, and it uses an electric motor to rotate the main mass
columns.
To accomplish the mass lifting, selection and lowering function, the AMH mass handler uses
four main sub-systems.
•
Electronic and electrical controls (7): The AMH electronic and electrical controls are
located just above the mass lifter, under a protective cap. These support the AMH
operating logic, a proximity sensor to detect mass load position, reading of the main
mass selection column switches, operation of the column rotating motor and actuation of
the pneumatic control solenoid valves.
•
Mass lifter (8): The mass lifter is used to lift the entire mass load up to the mass
selection position and then to lower the selected masses onto the piston. The mass lifter
is pneumatically driven. A flexible diaphragm (4) is connected to a lifting assembly (5). A
three-way solenoid valve (9) is actuated to admit or exhaust drive air pressure to and
from the volume under the diaphragm. Admitting drive pressure pushes the lifting
assembly up. Exhausting the pressure lowers it. The pressure is exhausted outside of
the vacuum chamber, to the AMH drive vacuum supply line.