PST MICHELL Instruments MDM300 User manual

MDM300 I.S.
Advanced Dew-Point Hygrometer
User Manual
97213 Issue 6.4
February 2023
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© 2023 Michell Instruments
This document is the property of Michell Instruments Ltd and may not be copied or
otherwise reproduced, communicated in any way to third parties, nor stored in any Data
Processing System without the express written authorization of Michell Instruments Ltd.
MDM300 I.S.
Advanced Dew-Point Hygrometer
(for use in hazardous areas)
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MDM300 I.S. User Manual
Contents
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MDM300 I.S. User Manual
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39
Appendices
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58
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MDM300 I.S. User Manual
Figures
Tables
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21
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25
29
32
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MDM300 I.S. User Manual
Safety
!
Electrical Safety
NOTE: No battery charger unit other than that supplied with the instrument should be
used.
NOTE: Do not allow the battery to fully discharge.
NOTE: The Um value is less than 250V and must only be connected to a source complying
with IEC6050 series, IEC 61010-1 or equivalent standard.
!
Pressure Safety
!
Toxic Materials
Repair and Maintenance
Calibration
Safety Conformity
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MDM300 I.S. User Manual
Abbreviations
W
Warnings
Where this hazard warning symbol appears in the following
sections it is used to indicate areas where potentially
hazardous operations need to be carried out.
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MDM300 I.S. User Manual
1
INTRODUCTION
1 INTRODUCTION
° °
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MDM300 I.S. User Manual
2
INTRODUCTION
Figure 1
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MDM300 I.S. User Manual
3
INTRODUCTION
1.1 Controls and Indicators
Figure 2
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MDM300 I.S. User ManualINTRODUCTION
Item Panel Description
1
2
3NOTE: The instrument does not need be switched ON
in order to charge the internal NiMH battery.
5
NOTE: The hinged rubber protection cover should be
kept closed when the connector is not in use.
7
!
Connection to the battery charger should
always be made in a safe area - never in a
hazardous area environment
!ONLY USE THE CHARGER PROVIDED
!Never allow the battery to fully discharge
Table 1
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MDM300 I.S. User ManualINTRODUCTION
1.3 Instrument Display
Figure 3
Item Description
1
Secondary display
2
Battery charge indicator icon
NOTE: The icon becomes animated when the charger is connected.
3Keyboard beep indicator
Keyboard lock indicator
5Datalog status indicator
Sensor initializing indicator
7
Primary display
8Status message display area
Table 2
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MDM300 I.S. User Manual
7
INTRODUCTION
1.3.1 Display Units
Absolute Humidity
•
•3
•3
Moisture Content
•
•
•2 2 2
Dew Point
•
• °F
•
Relative Humidity (%)
Mixing Ratio
•2 2 2
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MDM300 I.S. User Manual
8
INTRODUCTION
1.3.2 Status Display Indications
‘
<
°
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MDM300 I.S. User Manual
9
INSTALLATION
2 INSTALLATION
2.1 Safety
!It is essential that the installation of the electrical and
personnel.
2.2 Unpacking the Instrument
12
3
Figure 4
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MDM300 I.S. User ManualINSTALLATION
2.3 MDM300 I.S. Accessories
NOTE: On delivery the two large orifice adaptors are fitted into the instrument’s
gas ports (1 and 2) as shown in . One small orifice adaptor is provided
as a loose spare in the accessory pack (see Section 2.5).
Figure 5
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MDM300 I.S. User Manual
12
INSTALLATION
2.4 Operational Requirements
2.4.1 Environmental Requirements – MDM300 I.S. Instrument
2.4.2 Charger Electrical Requirements
2.5 Instrument Gas Connections
!
POSSIBLE INJURY! The tubing, valves and other apparatus
attached to this instrument must be adequate for the
maximum pressure which will be applied, otherwise physical
injury to the operator or bystander is possible.
A
Dew point at Gas Inlet port Gas Outlet port Sample gas
pressure
Table 3
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