Oldham MX 52, Руководство по пусконаладке, эксплуатации и техническому обслуживанию

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5.2.2. Copy
In order to make the programming of ALL CHANNELS less TIME-CONSUMING when the same
programming is required for a number of channels, it is recommended that the “COPY” menu
should be used (see Section IV-2 on Menus) by means of the keypad and the “Programming” key.
Then, the instructions in this menu should simply be followed.
5.3.
Calibrations
Gas detection instruments are potential life-saving devices. Recognizing this fact, OLDHAM
Corporation recommends that a functional “bump” test be performed on every fixed gas-monitoring
instruments as part of a regular maintenance program. A functional test is defined as a brief
exposure of the detector to a concentration of gas(es) in excess of the lowest alarm set-point for
each sensor for the purpose of verifying sensor and alarm operation and is not intended to be a
measure of the accuracy of the instrument.
OLDHAM further recommends that a full instrument calibration be performed using a certified
concentration(s) of calibration gas(es) quarterly, every 3 months.* Calibrations may be necessary
more or less frequently based, for example, on application, field conditions, exposure to gas, sensor
technology, and environmental conditions. The frequency of calibration is best determined by
company policy or local regulatory agencies.
If an instrument fails to operate properly during any functional “bump” test, a full instrument
calibration should be performed successfully prior to use.
These recommendations are based on safe work procedures, industry best practises, and regulatory
standards to ensure worker safety. OLDHAM is not responsible for setting safety practices and
policies.
*
For new installations it may be prudent to carry out bump tests frequently at first (perhaps
weekly), increasing the time intervals (to, perhaps, monthly or more) as confidence grows with
experience in the installation concerned, on the basis of the maintenance record.
Case 1
Measuring channel connected to a detector with no integrated electronics (explosive gas
detector).

Prepare the detector for calibration:
- Calibration consists in adjusting the detector ZERO in PURE AIR and its sensitivity to
the STANDARD GAS.
- If the detector zero is set with natural diffusion in pure air, the surrounding atmosphere
must be calm (wind speed of less than 1 m/s).