Teledyne UA-6, Инструкция по установке и эксплуатации

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UA-6 Detector
Section 5 Maintenance and Adjustment
5-7
b. Optical unit has an imbalance greater than
0.5 absorbance units. b. Set the UA-6 to “SET LAMP & OPTICS”
and adjust the baseline control on the optical
unit until the chart pen zeros. If the chart pen
is below 0% of scale, there is a problem with
the reference side of the optical unit. Move
the baseline adjust aperture out of the light
path and check the reference flowcell and fil-
ter for obstructions. If the chart pen is near
100% of chart and can not be zeroed with
the optical unit baseline adjust, there is an
obstruction in the measuring flowcell or filter.
Remove the obstruction.
3. Unstable or noisy
baseline when using a
Type 11 optical unit
(Table 5-2, item 4). a. Normal noise more noticeable on sensi-
tive ranges. a. Turn the NOISE FILTER to reduce noise.
b. Lamp current needs to be changed. b. Some lamps’ current becomes unstable or
indicates a step characteristic, as observed
on the recorder. Decrease the lamp current
until the step characteristic disappears. Do
this by moving the internal jumper S401
inside the UA-6.
c. No flow cell in the Type 11 optical unit
REFERENCE CELL B light path (refer to
Section 2.6). c. Install the same type of flow cell in the
REFERENCE CELL B light path as in MEA-
SURING CELL A light path to improve the
optical balance.
d. Unstable UV lamp in the optical unit dur-
ing “coldroom” operation. d. Turn the COLDROOM HEATER switch to
ON.
e. Unstable UV lamp in the optical unit. e. Replace the UV lamp following the proce-
dure in Section 5.6.1.
f. Condensation on the flow cell windows. f. For the Type 11 optical unit, turn the
COLDROOM HEATER switch to ON.
g. Liquid leaking across the flow cell win-
dows. g. Repair the leakage following the proce-
dure in Section 5.7.2
h. Temperature fluctuations in the “coldroom”
at temperatures below 10°C. h. Turn the COLDROOM HEATER switch to
ON.
i. Draft or air currents hitting a Type 11 opti-
cal unit.
This is more noticeable in the more sensitive
ranges (0.002, 0.005, 0.01, 0.02, and 0.05)
.
i. Shield, insulate, or remove the optical unit
from the air currents.
j. When operating in the 0.002, 0.005, 0.01,
0.02, and 0.05 ranges, there is noise and
drift. j. Make allowances for the normal noise and
drift (refer to Table 1-1 “Noise Specifications”
for detailed specifications).
k. Fluctuations in pressure or flow rate
through the flow cell causing noise and drift
problems. Noticeable when using reciprocat-
ing pump. k. Increase the RISE TIME. Remove the
reciprocating pump from the system, and
use another type (e.g. Teledyne Isco syringe
pump) or install a pulsation damper in the
flow system.
Table 5-1 Baseline Troubleshooting (Continued)
Problem Probable Cause Solution