Rosemount 7D, Инструкция по эксплуатации

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T
HEORY
30
December 2000 Rosemount Analytical 748221-L Model 7D Thermal Conductivity Analyzer
90-
VOLT CENTER
-
TAPPED SECONDARY
Drives a rectifier circuit on the optional Current Output Board (PN 652816). The
transformer winding and the associated circuit constitute a floating power supply for
the emitter-follower stage. Refer to Section 5.2.3.
9.5 VAC
SECONDARY
Drives a +5 VDC supply not used in this instrument.
5.2.6 D
ETECTOR
B
LOCKS
There are two types of detector configurations; flowing reference and sealed nitrogen
reference. The sealed reference with nitrogen can be recharged by flowing nitrogen
through the reference and closing the plugs. Three filament types are available:
tungsten, Hitempco, and gold-sheathed tungsten.
5.2.7 C
ASE
T
EMPERATURE
C
ONTROLLER
A
SSEMBLY
The case Temperature Controller Assembly (PN 652270) maintains an approximate
117
°
F (47
°
C) temperature within the instrument.
Changes in case temperature affect the resistance of the sensor connected to J18.
This in turn changes the bias of amplifier AR1, which controls the input to the case
heater via switch U2. The heater receives power through pins 3, 4 and/or 5,
depending on the voltage selected at switch S3. A thermal fuse at J5 prevents the
case from overheating.
5.2.8 D
UAL
A
LARMS
(O
PTION
)
Instruments with optional Dual Alarms have two pots on the front door which are used
to select setpoints. The scales on the nameplate designate setpoints from 0 to 100%.
The alarm module is shown in Figure 7-2, and the factory connections are shown in
drawing 654642. The module plugs into a socket, which is part of a terminal block
mounted onto the chassis of the instrument. A marker on the alarm module indicates
the function of each socket pin.
This unit is factory configured and requires no user adjustment. Pins for AC power (1,
2, and 3), alarm setpoint control (8, 10, 18, and 19), and signal from analyzer circuitry
(7 and 9) are wired at the factory.
Connections of the remaining pins depend upon the application. The relays are rated
at 1.0 A, 120 VAC and 5.0 A, 120 VDC, form C, resistive loads.