Oldham OLC 20 User manual

USER MANUAL
OLC/OLCT 20
Part Number: NPO20GB
Revision: D.0
Gas Detector
The Fixed Gas Detection Experts

2
GAS DETECTION
We are delighted that you have chosen an OLDHAM instrument and would like to thank you for your
choice.
We have taken all the necessary measures to ensure that your instrument provides total satisfaction.
Now it is important to read this document carefully.
E
EX XT TE EN NT T O OF F R RE ES SP PO ON NS SI IB BI IL LI IT TY Y
* OLDHAM declines its responsibility towards any person for material damage, physical injury or death resulting
wholly or partly from inappropriate use, installation or storage of its equipment resulting from failure to observe
instructions and warnings and/or standards and regulations in force.
* OLDHAM neither supports nor authorises any company, physical or moral person to assume responsibility on
behalf of OLDHAM, even if it is involved in the sale of OLDHAM products.
* OLDHAM cannot be held responsible for direct or indirect damage or be required to pay direct or indirect
compensation resulting from the sale or use of any of its products IF THESE PRODUCTS HAVE NOT BEEN
DEFINED AND CHOSEN BY OLDHAM FOR THEIR SPECIFIC USE.
C
CL LA AU US SE ES S C CO ON NC CE ER RN NI IN NG G P PR RO OP PE ER RT TY Y
* Drawings, plans, specifications and information included in this document contain confidential information that is
the property of OLDHAM.
* None of this information may be reproduced, copied, divulged or translated, by physical, electronic or any other
means, nor used as the basis for the manufacture or sale of OLDHAM equipment or for any other reasons without
prior consent from OLDHAM.
W
WA AR RN NI IN NG GS S
* This document is not contractually binding. In the interests of its customers, OLDHAM reserves to modify the
technical specifications of its equipment without notice, in order to improve its performance.
* READ THIS MANUAL CAREFULLY BEFORE FIRST USE OF THE EQUIPMENT: this manual must be
read by any person who is or will be responsible for using, maintaining or repairing this equipment.
* This equipment will only provide the announced performance levels if it is used, maintained and repaired
according to OLDHAM directives, by OLDHAM personnel or by personnel approved by OLDHAM.
G
GU UA AR RA AN NT TE EE E
2 years guarantee in normal conditions of use on parts and technical labour, return in our workshops, excluding
consumables (sensors, filters, etc.)

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CONTENTS
1Description...................................................................................................5
1.1 General..........................................................................................................................5
1.2 Main characteristics of the various versions.................................................................5
1.3 Mechanical installation of the various versions............................................................6
2Wiring arrangements..................................................................................7
2.1 3-Wire version (OLC 20d, OLCT 20d)........................................................................7
2.2 2-wire versions (OLCT 20d).........................................................................................7
2.3 2-wire Intrinsic Safety versions (OLCT 20i)................................................................8
3Maintenance.................................................................................................9
3.1 Detector OLC 20...........................................................................................................9
3.1.1Calibration...............................................................................................................9
3.1.2Replacing a sensor on an OLC 20.........................................................................10
3.2 Transmitters OLCT 20................................................................................................10
3.2.1Calibration.............................................................................................................10
3.2.2Calibration specifications......................................................................................12
3.3 Replacing a sensor on OLCT 20.................................................................................12
3.4 Disposal of OLC(T) 20...............................................................................................12
4Spare Parts.................................................................................................13
4.1 OLC 20 flameproof gas detector ................................................................................13
4.2 OLCT 20 flameproof gas detector..............................................................................13
4.3 OLCT 20 Intrinsic Safety detector..............................................................................14
5Accessories .................................................................................................15
6Technical characteristics of OLC 20.......................................................17
7Technical characteristics of OLCT 20.....................................................17
8Specific Instructions for use in Explosive Atmospheres according to
European Directive ATEX 94/9/EC ........................................................19
8.1 Specifications for mechanical and electrical installation in Classified Areas. ...........19
8.1.1Flameproof detectors (d).......................................................................................19
8.1.2Intrinsic safety detectors (i) OLCT 20 i................................................................19

4
8.2 Metrological specifications for explosive gas and oxygen measurement detectors...20
8.2.1Technical Specifications and Special Instructions for explosive gas detectors....21
8.2.2Technical Specifications and Special Instructions for Oxygen detectors.............25
8.3 Markings.....................................................................................................................26
8.3.1Flameproof certified version: OLC 20d and OLCT 20 d......................................26
8.3.2Intrinsic safety version: OLCT 20 i ......................................................................26
9Recommendations .....................................................................................27
10 EU Declaration of Conformity.................................................................29

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1Description
1.1 General
OLC 20 gas detectors are catalytic type detectors intended for the detection of combustible
gases. They are flameproof certified (OLC 20d).
OLCT 20 gas detectors are 4-20 mA transmitters and are intended for the measurement of
combustible and toxic gases and oxygen. They are either flameproof certified (OLCT 20d)
or intrinsically safe certified (OLCT 20i).
OLC 20s and OLCT 20s are available in ¾ NPT or M25 screw fittings and are designed to
be attached on a junction box or any compatible generic transmitters.
1.2 Main characteristics of the various versions
OLC 20
OLCT 20
LEL
LEL
TOX/O2
Flameproof design
X
X
X
Intrinsic safety design
X
3-wire cable / Wheatstone bridge
X
3-wire cable / 4-20 mA output
X
2-wire cable / 4-20 mA output
X
Catalytic sensor
X
X
Electrochemical sensor
X
Replaceable sensor
X
Replaceable and pre-calibrated sensor
X
X

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1.3 Mechanical installation of the various versions
Please ensure you read the paragraph: Special Specifications for use in Potentially Explosive
Atmospheres in Accordance with European Directive ATEX 94/9/EC
See Appendix 1 for general installation instructions.
Figure 1 : Dimensions
A
Dimensions OLC/OLCT 20
Cable length 0.2 m
A

7
C
3
1
3 (+)
1 (-/S)
E
C
B
A
D
1
2
3
1 (S)
2 (-)
3 (+)
B
E
D
D
A
2Wiring arrangements
Please ensure you read the paragraph: Special Specifications for use in Potentially Explosive
Atmospheres in Accordance with European Directive ATEX 94/9/EC
2.1 3-Wire version (OLC 20d, OLCT 20d)
Figure 2
A
B
C
D
E
OLDHAM controller
OLC or OLCT 20
Grounding
Power supply
Signal (I)
2.2 2-wire versions (OLCT 20d)
Figure 3
A
B
C
D
E
OLDHAM controller
OLC 20 or OLCT 20
Grounding
Power supply
Power supply
Signal

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Hazardous area
Safe area
C
B
A
2.3 2-wire Intrinsic Safety versions (OLCT 20i)
Figure 4
A
B
C
OLDHAM controller
OLC 20 or OLCT 20
ZENER Barrier

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3Maintenance
The operations and adjustments described in this chapter must be performed
by authorized personnel only as they can affect the appliance's reliability in
detection.
It is prohibited to open the transmitter when energized
3.1 Detector OLC 20
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.
3.1.1 Calibration
On the controller
On the detector
Set the measuring channel to the calibration
position (alarm relays inhibited)
Proceed the zero and span
Set the measuring channel back to the
"normal" position and make sure that it is
working properly.
Apply the calibration cup and perform the
calibration in accordance with the procedure
defined during the training course provided
by OLDHAM or by an OLDHAM’s
authorized person

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3.1.2 Replacing a sensor on an OLC 20
When?
-When the sensor is damaged or cannot be calibrated
-On a preventive basis
How?
-Turn off the relevant measuring channel
-Remove the sensor to be replaced
-Replace it with a new sensor
-Turn on the channel back and check that it operates correctly
(see the following page for more information)
3.2 Transmitters OLCT 20
OLCT 20 gas transmitters are equipped with a pre-calibrated sensor and do not require any
adjustment on installation.
However, as gas detectors are safety equipment, it is recommended to bump test the complete
transmitter after a sensor replacement.
3.2.1 Calibration
After removing the sensor from the transmitter, perform the calibration by using the calibrating
bench provided for that purpose (see CALIBRO’s user manual).

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Procedure
On the controller
On the detector
Set the measuring channel to the calibration
position (alarm relays inhibited)
Set the measuring channel back to the
"normal" position and make sure that it is
working properly.
Rotate the sensor
module then
extract it
1
2
Once calibrated put the sensor back in place or
use a replacement sensor and reinstall the whole
assembly.
Loosen the
locking screw

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3.2.2 Calibration specifications
Calibration shall be performed outside classified areas and by using suitable
equipment that is described during the training course provided by OLDHAM
or by a person authorized by OLDHAM.
OLCT 20 sensor module
(LEL/TOX/O2)
3.3 Replacing a sensor on OLCT 20
When?
-When the sensor is damaged or cannot be calibrated.
-On a preventive basis.
How?
-Switch off the relevant measuring channel.
-Remove the sensor to be replaced.
-Replace it with a new, precalibrated unit.
-Switch the channel back on and check that it operates correctly.
3.4 Disposal of OLC(T) 20
Concerning the conservation, of the protection and the improvement of the
quality of the environment, as well as for the protection of the health of the
persons and the careful and rational use of natural resources, OLCT 20 has to be
the object of a selective collection for the electronic equipments and cannot be
scrapped with the normal domestic waste. The user thus has the obligation to
separate the OLCT 20 of the other waste so as to guarantee that it is recycled in a
sure way at the environmental level. For more details of the existing sites of
collection, contact the local administration or the distributor of this product.
- Adjustment of 0 in
clean air, using
potentiometer (item 1).
- Adjustment of
sensitivity (with
standard gas), using the
potentiometer (item 2).
item 1
item 2

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4Spare Parts
Use only genuine spares, otherwise the reliability of the equipment could be adversely
affected
4.1 OLC 20 flameproof gas detector
Flameproof replacement sensors
Part number
Replacement sensor (VQ1 –standard)
6313757
Replacement sensor (AP –poison resistant)
6313758
Catharometric sensor
6313759
4.2 OLCT 20 flameproof gas detector
Flameproof replacement sensors
Part number
OLCT 20, 0-100% LEL (VQ1)
OLCT 20, 0-100% LEL (AP)
OLCT 20, 0-100% vol. (catharometer)
OLCT 20 CO, 0 –100 ppm
OLCT 20 CO, 0 –300 ppm
OLCT 20 CO, 0 - 1000 ppm
OLCT 20 H2S, 0 –30 ppm
OLCT 20 H2S, 0 –100 ppm
OLCT 20 H2S, 0 - 1000 ppm
OLCT 20 NO, 0 –100 ppm
OLCT 20 NO, 0 –300 ppm
OLCT 20 NO, 0 - 1000 ppm
OLCT 20 H2, 0 - 2000 ppm
OLCT 20 NH3, 0 –100 ppm
OLCT 20 NH3, 0 - 1000 ppm
OLCT 20 O2, 0 - 0–30% vol.
6313685
6313974
6313687
6313690
6313691
6313692
6313695
6313696
6313697
6313698
6313699
6313700
6313706
6313707
6313708
6313710

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4.3 OLCT 20 Intrinsic Safety detector
INTRINSIC SAFETY SENSORS (SI)
Part number
OLCT 20 CO, 0 –100 ppm
OLCT 20 CO, 0 –300 ppm
OLCT 20 CO, 0 - 1000 ppm
OLCT 20 H2S, 0 –30 ppm
OLCT 20 H2S, 0 –100 ppm
OLCT 20 H2S, 0 - 1000 ppm
OLCT 20 NO, 0 –100 ppm
OLCT 20 NO, 0 –300 ppm
OLCT 20 NO, 0 - 1000 ppm
OLCT 20 NO2, 0 –10 ppm
OLCT 20 NO2, 0 –30 ppm
OLCT 20 SO2, 0 –10 ppm
OLCT 20 SO2, 0 –30 ppm
OLCT 20 SO2, 0 - 100 ppm
OLCT 20 H2, 0 –2000 ppm
OLCT 20 NH3, 0 –100 ppm
OLCT 20 NH3, 0 - 1000 ppm
OLCT 20 HCl, 0 –30 ppm
OLCT 20 HCl, 0 - 100 ppm
OLCT 20 HCN, 0 –30 ppm
OLCT 20 HCN, 0 - 100 ppm
OLCT 20 Cl2, 0 –10 ppm
OLCT 20 O3, 0 –1 ppm
OLCT 20 COCl2, 0 –1 ppm
OLCT 20 PH3, 0 –1 ppm
OLCT 20 AsH3, 0 –1 ppm
OLCT 20 HF, 0 –10 ppm
OLCT 20 ClO2, 0 –3 ppm
OLCT 20 ETO, 0 –30 ppm
OLCT 20 SiH4, 0 –50 ppm
OLCT 20 O2, 0 –30% vol.
6313711
6313712
6313713
6313716
6313717
6313718
6313719
6313720
6313721
6313722
6313723
6313724
6313725
6313726
6313727
6313728
6313729
6313730
6313731
6313732
6313733
6313734
6313735
6313736
6313737
6313738
6313739
6313740
6313746
6313747
6313748

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5Accessories
TOOL KIT
6147869
CALIBRATION CUP
6331141
BY-PASS ADAPTOR
for combustible gases, CO, H2S, O2
6327910
PLASH GUARD
6329004
PROTECTIVE FILTER, PTFE
6335975
ACTIVE CARBON FILTER
6335976
REMOTE CALIBRATION CUP
(for combustible gases only)
6327911

16

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6Technical characteristics of OLC 20
Power supply: voltage on detector terminals = 2.8 V max
Power consumption: 3-wire version = 400 mA max
Measurement signal: Wheatstone bridge
Line length (shielded cable): 3-wire version = 1 km as 3x 1.5 mm2
(32 ohms in loop mode)
Output signal mV bridge output, 3 wires
Ingress Protection IP66
Weight 800 g
Dimensions 60 X 120 mm
7Technical characteristics of OLCT 20
A) Explosion-proof version
Power supply: voltage on detector terminals = 15 V to 30 V
Power consumption: 3-wire version = 100 mA
2-wire version = 25 mA
Load resistance: maximum resistance = 250 ohms
Line length (shielded cable): 3-wire version = 1 km as 3x 1.5 mm2(32 ohms in
loop mode)
2-wire version = 4 km as 3x 1.5 mm2(32 ohms in
loop mode)
B) Intrinsic safety version
Characteristics of ZENER barrier: 28 V - 300 ohms
Supply voltage for barrier: 19 V to 26 V
Voltage on detector terminals: 10 V to 26 V
Power consumption: 25 mA max
Load resistance: 47 ohms
Line length (shielded cable): 1 km as 3x 1.5 mm2 (32 ohms in loop mode)
Output signal
Source mode current 4-20 mA
Max. current 25 mA
Fault current <1 mA
Miscellaneous
Ingress Protection IP66
Weight 800 g
Dimensions 60 X 120 mm

18

19
8Specific Instructions for use in Explosive Atmospheres
according to European Directive ATEX 94/9/EC
The OLC/OLCT 20 gas detectors comply with the requirements of European Directive ATEX
94/9/EC relating to explosive Dust and Gas atmospheres.
As a result of their metrological performance, as tested by the Approval Agency INERIS, the
OLC/OLCT 20 gas detectors designed to measure explosive gasses and oxygen are classified as
safety devices and may therefore contribute to limiting the risk of explosion.
The information contained in the following paragraphs should be respected and taken into
account by the manager of the site where the equipment is installed. Please refer to the provisions of
European Directive ATEX 1999/92/EC on improving health and safety conditions for workers
exposed to potentially explosive atmospheres.
8.1 Specifications for mechanical and electrical installation in Classified Areas.
Installation will comply with all applicable standards, and particularly with EN 60079-14 and
EN 60079-17.
8.1.1 Flameproof detectors (d)
-These detectors are intended for use in surface industries II, Category 2, zones 1 and 2
(Gas) and zones 21 and 22 (Dust) in ambient temperature from -20°C to +70°C.
-Cables will be mechanically protected.
-The transmitter casing will be earthed using the external or internal terminal, which
should be corrosion-protected. Users should clean detectors regularly in order to prevent
any external accumulation of dust.
-Mechanically, detectors will be installed such that the detection sensor points downwards.
Any variance of over 45° from the vertical will result in measurement errors.
-Where connections are located in a classified zone, they will be enclosed in approved
envelopes.
-The width of the threaded joint of cable gland is superior to the value specified in the table
of EN 60079-1 standard.
8.1.2 Intrinsic safety detectors (i) OLCT 20 i
-These detectors are intended for use in surface industries II, Category 1, zones 0, 1 and 2
(Gas) and zones 20, 21 and 22 (Dust). They are also intended for use in coal mines,
Category M1. The ambient operating temperature range is –20°C to +70°C.
-Users should clean detectors regularly in order to prevent any external accumulation of
dust.
-The person responsible for IS installation (the “System Designer”) must draw up a system
document demonstrating that every aspect of the Power Cable Detector system complies
with intrinsic safety.
-They must be powered by an intrinsic safety source: 28V - 300 ohms
-Where connections are located in a classified zone, they will be enclosed in approved
envelopes.
-The safety parameters applying to the OLCT 20i detectors are :
Ui (V)
Ii (mA)
Pi (mW)
Ci (nF)
Li (H)
28
94
658
40
15μH

20
8.2 Metrological specifications for explosive gas and oxygen measurement
detectors
In case of exposure above the measuring range, it is mandatory to bump test
the instrument with gas and/or to perform a calibration.
In the event of a change of position, it is necessary to re-calibrate the detector.
The OLC/OLCT 20 transmitter sensors intended to measure explosive gasses and oxygen are
classified as safety devices and may therefore contribute to limiting the risk of explosion.
Detectors comply with the following European standards:
Explosive gas detectors:
-OLC 20 explosive gas detectors comply with European standards EN 50054 and EN
50057 for Methane (calibration gas), Propane and Hydrogen (gasses following response
curves) where they are used with the following OLDHAM controllers SV 4B, MX 15,
MX 32, MX 42A, MX 43, MX 48 and MX 52.
-OLCT 20 explosive gas detectors comply with European standards EN 50054 and EN
50057 for Methane (calibration gas), Propane and Hydrogen (gasses following response
curves), where they are used with SV 4B, MX 15, MX 32, MX 42A, MX 43, MX 48, MX
52 and MX 62 OLDHAM controllers, or where they are connected to measurement
devices with 4-20 mA inputs in accordance with paragraph 1.5 of Appendix II of the
ATEX 94/9/EC Directive and are compatible with their characteristics (cf. transfer curve).
Oxygen detectors:
-OLCT 20 oxygen detectors comply with European Standard EN 50104 where they are
used with MX 15, MX 32, MX 42A, MX 43, MX 48, MX 52 and MX 62 OLDHAM
controllers, or where they are connected to measurement devices with 4-20 mA inputs in
accordance with paragraph 1.5 of Appendix II of the ATEX 94/9/EC Directive and are
compatible with their characteristics (cf. transfer curve).