Teledyne 2000XTC - Thermal conductivity analyzer - Manual (Page 27)

Thermal Conductivity Transmitter Installation
INSTRUMENT USE ONLY AN APPROVED
INTERCONNECTION CABLE. SEE THE SPARE
PARTS LIST IN THE APPENDIX OF THIS MANUAL
FOR AN APPROVED FACTORY REPLACEMENT
CABLE.
For intrinsically safe installation, use only the cable supplied by the
factory. Run length should not exceed 30.5 meters (100 ft).
3.6 Calibration
Note: Calibration frequency of the 2000XTC is highly dependent
on gas application. The recommended frequency is once
per month, although specific applications may be able to
go longer without required calibration. Perform calibration
procedure as required for your application, or contact the
manufacturer for more information.
Once the modules have been properly installed and wiring is
secure, check the following before calibrating the transmitter:
Make sure that suitable sources of zero and span gas are
connected to the transmitter either via a switching manifold
or separately (zero followed by span gas). See section 2.3. •
•
•
•
Check the integrity and accuracy of the gas connections.
Make sure there are no leaks.
Verify that the modules have been properly installed and
wiring is secure.
Check that inlet sample pressure and flow rate is within the
accepted range (see section 3.3).
Calibration involves setting the zero level followed by setting the
span of the instrument. Zero and span potentiometers are located under
the cover of the transmitter on the PC board as shown in Figure 3-5.
The following calibration procedures assume that suitable
calibration gas connections have been made and that a read-out device
capable of interpreting a 4-20 mA current is attached to the output
terminals of the galvanic isolator module (see Section 3-5).
Teledyne Analytical Instruments 17