Ametek WDG-V, Руководство пользователя

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PN 9000-133-VE, Rev U
Diagnostics Flowcharts
This section describes how to check different analyzer areas for possible prob-
lems. See also “Alarm and Warning Messages” in this chapter for help on what
checks you should perform based on the error message displayed. If no error
messages are displayed, but the readings do not appear to be accurate, review
the section “General Troubleshooting” in this chapter.
AMETEK recommends monitoring the Thermocouple millivolts and Cell mil-
livolts displayed during troubleshooting as a troubleshooting aid. This infor-
mation will be helpful should you need to contact the factory for assistance. Be
sure to always include your analyzer model and serial number when contact-
ing AMETEK for technical support.
Exercise care when working on the analyzer. Turn off power, allow the
unit to cool, and wear gloves.
Thermocouple Checks
Problem/Possible Cause Corrective Action
Open Thermocouple Remove power to the analyzer. Measure across terminals +TC-
on the
Sensor
board with an ohm meter. If an open circuit is
measured, replace the Thermocouple .
Shorted/Failed Thermo-
couple
Check that the Thermocouple leads are not shorted to chassis
ground by using an Ohm meter to measure between terminal
TC+
on the
Sensor
board and chassis ground, and between
terminal TC- on the Sensor board and chassis ground. If shorted,
replace the Thermocouple .
To verify the operation of the Thermocouple itself, remove the
Thermocouple from the analyzer and heat its ceramic tip to a
known temperature. Measure the millivolt output with a proper
temperature indicating meter (Type K Thermocouple). If the
Thermocouple reads inaccurately, replace it.
Reversed Thermocouple
Wires
First, view the Cell temperature via the HOME screen or Di-
agnostic
screen. If the Thermocouple leads are reversed, the
displayed temperature will be decreasing as the analyzer warms
up (this will usually happen at start-up or after you replace a
Thermocouple). This indicates that the Thermocouple wiring is
reversed. If you just replaced a Thermocouple, check the leads
from the Thermocouple to the
Sensor
board: Yellow wire con-
nects to terminal
TC (+)
, Red wire connects to terminal
TC (-)
.
3-6 | Thermox
®
WDG-V / VC / VCM / VM