Rosemount 755, Instruction Manual

Page: 41 / 94

3
S
TARTUP
748183-H
3-1
Rosemount Analytical
November 1997
Preparatory to start-up and calibration, a familiarization with Figures 1-1, 1-2 and 3-1, and
Tables 3-1 is recommended. These figures give locations and summarized descriptions of
components and operating adjustments of the Model 755.
Open analyzer door and verify that circuit boards are properly installed and connected.
Verify proper connection of electrical cables, see Figure 2-1.
3.1 START-UP PROCEDURE
If explosive gas samples are introduced into the analyzer, it is recommended
that sample containment system fittings and components be thoroughly leak
checked prior to initial application of electrical power, routinely on a periodic
basis thereafter, and after any maintenance which entails breaking the integrity
of the sample containment system. Leakage of flammable sample gas could
result in an explosion.
Pass suitable on-scale gas (not actual sample) through the analyzer. Turn on power. If
meter drives off-scale in either direction, the probable cause is hang-up of the
suspension within the detector assembly. To correct this condition, turn off power, tap
detector compartment with fingers, wait 30 seconds, then again apply power.
When on-scale reading is obtained, allow analyzer to warm up for at least one hour
with gas flowing. This warm-up is necessary because a reliable calibration is
obtainable only after the analyzer reaches temperature stability. Moreover the
resultant elevated temperature will ensure against condensation within, and possible
damage to, the detector assembly.
After analyzer warm-up, the meter or recorder should give stable,, drift-free readout. If
so, proceed to Section 3.2. Otherwise refer to Section 7, Service and Maintenance.
3.2 CALIBRATION
Calibration consists of establishing a downscale calibration point and an upscale
calibration point, see Table 3-3. Downscale calibration may be performed on the range
that will be used during sample analysis. For maximum precision however, it should be
WARNING: POSSIBLE EXPLOSION HAZARD