Oldham MX 52 User manual

Installation manual
MX 52
MEASURING UNIT
Part Number: NP52IGB
Revision: B.0
The Fixed Gas Detection Experts

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Copyright April 2016 by Oldham S.A.S.
All rights reserved. The reproduction of all or any section of this document in any form
whatsoever without the written permission of Oldham S.A.S. is forbidden.
The information contained in this manual is accurate to our knowledge.
As a result of continuous research and development, the specifications of this product may be
modified at any time without prior notice.

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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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C O N T E N T S
1. INSTALLATION AND CONNECTIONS ...................................................................7
1.1. INSTALLATION : RECOMMENDATIONS........................................................7
1.2. ELECTRICAL CONNECTIONS FOR THE MX52 FACILITY (Fig.8) ...............7
1.2.1.AC supply................................................................................................................7
1.2.2.DC supply................................................................................................................8
1.3. THE SENSORS (Fig. 9 –Fig. 12) ..........................................................................8
1.3.1.. Explosimetric detectors of PONT type..........................................................8
1.3.2.3-wire detectors 4-20 mA: 3 connecting wires for shielded cable..........................9
1.3.3.2-wire detectors 4-20 mA: 2 connecting wires for shielded cable..........................9
1.3.4.FIRE detectors: 2 connecting wires for shielded cable...........................................9
1.3.5.FLAME detectors: 2, 3 or 4 connecting wires for shielded cable depending on
utilization.................................................................................................................9
1.3.6.CO2 detector of type “Ventostat VT” ...................................................................11
1.3.7.Specific case of CTX100 / COX 100 intrinsic safety detectors............................11
1.3.8.Other detectors with standardized current output..................................................11
1.3.9.Parking application................................................................................................12
1.4. Connecting the unit to external devices ................................................................12
1.4.1. Slaving controls .......................................................................................................................... 12
1.4.2. 4-20 mA current outputs (Fig. 12) .............................................................................................. 13
1.4.3. RS 232 and RS 485 outputs ........................................................................................................ 13
1.4.4. Remote acknowledgement.......................................................................................................... 14
2. SWITCHING ON .........................................................................................................15
2.1. CHECKING THE INSTALLATION....................................................................15
2.2. SWITCHING ON THE FACILITY......................................................................15
2.3. OPERATING MODES .........................................................................................16
2.3.1. Buzzer......................................................................................................................................... 16
2.3.2. Light-emitting diodes (LEDs) (fig26)......................................................................................... 16
2.3.3. Alarm thresholds......................................................................................................................... 16
2.3.4. The measurement facility............................................................................................................ 17
3. USE.................................................................................................................................19
3.1. LIST AND FUNCTION OF THE VARIOUS “USER” ELEMENTS FOR
PROGRAMMING AND CALIBRATING THE FACILITY...............................19
3.1.1. The keypad (see Fig.26 and 4).................................................................................................... 19
3.1.2. The maintenance keys................................................................................................................. 20
4. SCRAPPING OF MX52...............................................................................................21
5. SPECIAL SPECIFICATIONS FOR USE IN POTENTIALLY EXPLOSIVE
ATMOSPHERES IN ACCORDANCE WITH EUROPEAN DIRECTIVE ATEX
94/9/EC....................................................................................................................................23
5.1. SPECIFICATIONS FOR MECHANICAL AND ELECTRICAL
INSTALLATION IN CLASSIFIED AREAS.......................................................23

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5.2. METROLOGICAL SPECIFICATIONS...............................................................23
5.3. CONNECTING DETECTORS OTHER THAN OLDHAM DETECTORS TO
THE MX52 DEVICE............................................................................................ 24
5.3.1. Device transfer curves in 0% to 100% LEL configuration ......................................................... 24
5.3.2. Device transfer curves in 0% to 30.0% OXYGEN configuration............................................... 25
5.3.3. Power supply and load resistance characteristics........................................................................ 25
5.4. MARKING...........................................................................................................25
6. VIEWS DEPICTED IN THE LEAFLET...................................................................29

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1
1. . I IN NS ST TA AL LL LA AT TI IO ON N A AN ND D C CO ON NN NE EC CT TI IO ON NS S
Please ensure you read the paragraph: Special Specifications for use in Potentially Explosive
Atmospheres in Accordance with European Directive ATEX 94/9/EC
1.1. INSTALLATION : RECOMMENDATIONS
The MX52 facility can be installed anywhere away from an explosive atmosphere. It should
preferably be sited in a ventilated location under surveillance (guard post, control room,
instrumentation room, etc.)
Fixing is carried out in accordance with the dimensions of Figure 1 (4 fixing points).
NOTE :
In order to be able to fully open the pivoting front panel of the facility, allow for opening by
rotating 180° downwards.
To make any connections, switch off the facility using the general ON / OFF switch located at
the bottom left of the FRONT circuit (see Fig.4 and Fig.26)
1.2. ELECTRICAL CONNECTIONS FOR THE MX52 FACILITY (Fig.8)
The facility is equipped with an automatic switching device for connecting to the 24 V DC
voltage should the 220 V AC mains voltage be absent, and hence it is possible to use
inexpensive backup power supplies.
1.2.1. AC supply
-Voltage : 230 V AC (207 to 224 V) 50/60 Hz
-Maximum power : 300 VA
-maximum current in the cable = 1.5 A
-Cable = 3 x 1.5 mm2 (earth included)
-Location of connection terminals : Fig. 8 ref A
-Protection : the phase and neutral wires are protected by time –delay 2A fuses
located at the rear of the power module (Fig.8 ref B)
-Voltage : 103 to 122 V AC –50/60 Hz optional
ATTENTION
It is absolutely essential for the apparatus to be earthed. A terminal is reserved for this
purpose et the rear of the power module : fig.5. this earthing is necessary to ensure the proper
operation of :
-- the mains interference suppression filter
-- the devices for protection against electromagnetic interference.

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1.2.2. DC supply
-Voltage : 21 to 30 volts DC. The “minus” of the DC supply is earthed (and the
earth is linked to the chassis).
-Maximum power : 240 W
-Maximum current in the cable : 12.5 A
-Cable = 2 x 2.5 mm2 or 2 x 4 mm2 depending on the length.
-Location of the terminal : Fig.8 ref : D page
-Protection : via 2 fuses located et the rear of the supply module (Fig 8 –ref : E)
1.3. THE SENSORS (Fig. 9 –Fig. 12)
NOTE :
-The sensors are linked by SHIELDED cables.
-The use of shielded cables is OBLIGATORY
-The ground braid of the shielded cables must be earthed at one end
1.3.1.. Explosimetric detectors of PONT type
Three connecting wires for a shielded cable.
-Resistance of detector / unit cable: 16 ohms maximum per wire, i.e. 32 ohms in
loop (1 km for cable 3 x 1.5 mm²).
-Connection on MX52 unit: see Fig. 10
ATTENTION
Each channel has been configured in the factory for one type of sensor (explo. Gas, toxic
gas, fire or flames).
Interchanging two types of sensor will lead to the destruction of the central board or of the
sensor.

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1.3.2. 3-wire detectors 4-20 mA: 3 connecting wires for shielded cable
-Resistance of detector / unit cable: 16 ohms maximum per wire, i.e. 32 ohms in
loop (1 km for cable 3 x 1.5 mm²).
-Connection on MX52 unit: see Fig. 10.
1.3.3. 2-wire detectors 4-20 mA: 2 connecting wires for shielded cable
-Resistance of detector / unit cable: 32 ohms maximum per wire, i.e. 64 ohms in
loop (2 km for cable 2 x 1.5 mm²).
-Connection on MX52 unit: see Fig. 11.
1.3.4. FIRE detectors: 2 connecting wires for shielded cable
The current commercial designations are as follows:
-“Thermovelo” detectors of type EC 11 (sensitive to temperature variations)
-Ionic detectors of type EI 1 100 (sensitive to smoke)
-Optical detectors of type EO 1 100 (sensitive to smoke)
-Resistance of detector / unit cable: 28 ohms maximum per wire, i.e. 56 ohms in
loop (2 km for cable 2 x 1.5 mm²)
-Fire detectors can be detected in parallel to a maximum of five. The end-of-loop
resistor (2.7 K) is to be placed at the end of the line on the last detector.
-Connection on MX52 unit: see Fig. 11
1.3.5. FLAME detectors: 2, 3 or 4 connecting wires for shielded cable
depending on utilization
REMARK
The detectors can be supplied with power either via the MX52 unit or by an auxiliary 24 V
DC source.
These detectors can operate in standalone mode:
24 V DC power supply and direct utilization of relay contacts in accordance with the technical
specification corresponding to the detector used.

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The current commercial designations are as follows:
-model 20/20 U - analog - type UV - 752002 (sensitive to UV radiation)
-model 20/20 UC - analog - type UV (sensitive to UV radiation)
-model 20/20 UB - µP technology - type UV - 772002 (sensitive to UV radiation)
-model 20/20 UBC - µP technology - type UV (sensitive to UV radiation)
-model 20/20 LC - analog - type UV/IR (pyroelectric, combination of UV and IR
detectors)
-model 20/20 LBC - µP technology - type UV/IR (pyroelectric, combination of UV
and IR detectors)
-model 20/20 I - µP technology - triple IR detector - 780002 (pyroelectric, sensitive
to IR radiation)
These detectors are equipped with various types of terminal block (see table below).
Model
20/20 U
20/20 UC
20/20 UB
20/20 LC
20/20 UNC
20/20 LBC
20/20 I
Type
of terminal
block
B
C
A
C
C
C
A
-Resistance of cable / unit
-In the case of local 24 V DC power supply : 8.5 ohms maximum per wire, i.e. 17
ohms in loop
-In the case of power supply via the MX48 unit : 3 ohms maximum per wire, i.e. 6
ohms* in loop
4 ohms for detector 20/20 I (IR3)
-Connection on MX52 unit (ONE detector per measuring channel ONLY):
-detector equipped with a terminal block of type A: see Fig. 13
-detector equipped with a terminal block of type B: see Fig. 14
-detector equipped with a terminal block of type C: see Fig. 15
Example of the utilization of the 4-20 mA signal from flame detectors equipped with
connectors of type A or C: see Fig. 16.
Example of the utilization of detectors equipped with connectors of either type A or type B
and with auxiliary power supply. The auxiliary power supply must be able to supply power to
the number of detectors planned in the measuring loop (see Fig. 17).
REMARK
In the case of this application, the maximum of 3 flame detectors can be connected in the
measuring loop.
Example of the utilization of IR3 or UV/IR detectors equipped with connectors of type A with
a local junction box and galvanic insulation (see Fig. 18).