Critical Environment Technologies LPT-M, Руководство по эксплуатации

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© 2020 All rights reserved. Data subject to change without notice. 55
Rev. B | 2020.11 LPT-M - Operation Manual
Equipment: Calibration Kit, Calibration gases, digital multi-meter, magnetic wand
Users can order the calibration kit, calibration accessories and / or gases from any CETCI authorized
distributor or you can supply your own gas and equipment as long as the gas meets the minimum
specifi cations. CETCI does not ship gas cylinders outside of Canada.
7.1.5 Gas Testing Frequency (Bump Testing)
For the purpose of safety in OHS applications, sensors should be gas tested (bump tested) once
every month to confi rm response and alarm activation.
7.1.6 Sticky Gases
Sticky gases, such as Ozone (O
3
), Chlorine (Cl
2
) and Hydrogen Chloride (HCl) adhere to surfaces
including tubing and splash guar ds. When calibrating a sticky gas sensor we suggest using Tefl on
lined tubing so the gas doesn’t adhere to the tubing, reducing the concentration of the fl ow of gas.
Also keep the length of the tubing as short as possible, no more than 0.91 to 1.22 m / 3 - 4 ft so
the gas fl ow concentration doesn’t lessen over the distance from the gas cylinder to the sensor.
If a splash guard is required for an LPT
-M Modbus® Transmitter with an Ozone, Chlorine, Chlorine
Dioxide, Hydrogen Chloride, Hydrogen Cyanide or Phosphine sensor the special sticky gas splash
guard (Option -SN) must be ordered.
It is also suggested that when calibrating a Chlorine sensor, you use a chlorine gas generator due
to the instability of Chlorine gas in a cylinder and the fact that it is diffi cult to get accurate readings
from that source.
7.1.7 Non-Intrusive Calibration
Calibration can normally performed without opening the unit by using a magnetic wand to engage
the magnetic sensors that are on the side of the enclosure. Refer to Section
4.1 Exterior Enclosure
for location photo. This is particularly useful if in a wet or dirty environment. A magnet of suffi cient
strength will be required to trip the sensors. Such a magnet is included in the Calibration Kit