Hach 1950Plus, Инструкция по эксплуатации инструмента, Страница: 129 / 188

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UVTOCTroubleshooting and Service.fm
Troubleshooting and Service Menus
Section 8 Troubleshooting and Service Menus
8.1 Preliminary Check
Before referring to the troubleshooting guide, make a routine check for
simple problems:
1. Confirm proper electrical power to the analyzer.
2. Check the fuses.
3. Verify that liquid and gas supplies are present and adequate.
4. Check all drains, sample, and gas lines to make sure that there are no
kinks, restrictions, or leaks.
If necessary, refer to the flow diagram, Figure 53 .
8.2 Troubleshooting
DANGER
The tasks presented in this section of the manual may have hazards—including
electrical shock—associated with them. Because they require specialized
training and knowledge, they should only be performed by qualified personnel.
CAUTION
Remove power to the relays before performing tasks in this manual section.
Depending on how the relays are configured into your data communication
system, disconnecting power may cause a fault condition to be seen.
Important Note: Delicate internal electronic components can be damaged by static
electricity, resulting in degraded instrument performance or eventual failure.
8.2.1 Instrument Does Not Calibrate
1. Check the flow by placing your finger over the IR cell outlet (vent) and
observing the GLS U–tube. Gas bubbles should circulate in the U–tube
from front to back.
Liquid tests requiring changes to the
plumbing should be done following
an analyzer flush to avoid contact
with samples and reagents.
2. Ensure that the overflow portion of the GLS is filled with water and is
draining. The U-tube in the GLS may provide a simple indication of a clog
or obstruction in the line containing the condenser and IR measurement
cell. Visually observe that the water level in the back-pressure gauge on
the GLS is at the operational level. An increase in pressure (caused by
the clog or obstruction) will push the level of the U-tube liquid seal down
on the right side until gas bubbles around the bottom of the U–tube
appear. If bubbles are forced through the drain, there is excessive back
pressure in the IR or vent line. Inspect and clean or replace the IR tubing.
3. In order to verify carrier flow integrity, the system should be flushed of all
sample and reagents for 15 minutes before continuing. Stop the analyzer.
Loosen the carrier flow supply on the UV manifold. Fold the carrier supply
tubing to obstruct flow or block with a fitting. The carrier flow should fall to
zero, as shown by the flow meter, and an alarm may be generated as the
reactor has been pressurized.
4. Fit a plug into the sparger block manifold outlet going to the resample
pump. Place the inlet to the resample pump into a new calibration
standard. In dilution analyzers it will be necessary to dilute the standard
by the dilution factor, normally 10. Tubing from the start-up kit may be