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4.

 

MAINTENANCE 

 

Prior  to  carrying  out  maintenance  or  service  operations  on  the  gas  detector, 
inhibit the safety function of the detector on the associated control unit or PLC 
and secure any output device connected to the system to  prevent false alarms 
and unintended actuations. 
Never open the detector when flammable gas is present. 
Regularly remove dust from the detector WITH A DAMP CLOTH ONLY to avoid 
the risk of electrostatic sparks. 

4.1.

 

Calibration 

Gas detectors must be calibrated at least once a year to mitigate the possible loss of sensitivity of 
the sensor. This calibration must be performed according to the procedure given by DALEMANS 
or his local representative, and in any case by qualified personnel who will have received a suita-
ble training. 

4.2.

 

Sintered metal filter replacement 

If  contamination  of  the  sintered  metal  filter  by  solvent,  gas  or  vapour  has  occurred,  the  sensing 
head must be replaced and the inspection frequency should be increased twofold. 

  Unscrew the sensing head top using the suitable tool OUT00000113. 

  Replace the sinter metal filter with a new one MEC00000010. 

  Screw the sensing head top back on again and tighten. 

  Make sure the sensing head is still correctly fastened to the junction box. 

  Perform calibration according to the procedure given by DALEMANS or his representative. 

4.3.

 

Sensing head replacement 

  Loosen the locking screw of the junction box cover using the 1.5 mm hex key. 

  Completely turn the cover counterclockwise to unscrew it. 

  On the terminal block, disconnect the two wires of the sensing head and remove the ferrite.  

  Unscrew  the  sensing  head  using  the  tool  OUT00000114  placed  between  the  base  and  the 

junction box. 

  Screw the new sensing head back on again and tighten. 

  Put the ferrite on the wires and reconnect them to the terminal block (see  

Figure 2): 

  RED wire on te 

  BLUE wire on terminal - 

  Screw the cover back onto the junction box and hand tighten ¼ turn. 

  Put the locking screw of the cover back in place and tighten with the 1.5 mm hex key. 

  Power on the detector and restore its safety function on the control unit or the PLC. 

  Perform calibration according to the procedure given by DALEMANS or his representative. 

 

 

Summary of Contents for DAT 420

Page 1: ......

Page 2: ...ever means without the prior written consent of DALEMANS s a is strictly forbidden All of the information contained in this document is non contractual and is subject to modification without warning D...

Page 3: ...Overview 8 2 2 Sensing head 9 2 3 Dimensions 10 3 INSTALLATION 11 3 1 Location 11 3 2 Mounting 12 3 3 Field wiring 13 3 4 Connection to a DALEMANS control unit 14 3 5 Connection to a Programmable Logi...

Page 4: ...nufacturer Maintenance must be performed according to the procedure given by DALEMANS or his local representative Maintenance or service attempts without observing these instructions or with out the a...

Page 5: ...ent Gas I Methane Intended for use in mines IIA Propane Intended for use in other locations than mines IIB Ethylene IIC Hydrogen Dust IIIA Combustible flyings IIIB Non conductive dust IIIC Conductive...

Page 6: ...Waste Electrical and Electronic Equipment WEEE These provisions are intended to preserve the natural resources used for manufacturing this product and to avoid the dispersion of substances poten tial...

Page 7: ...ous areas Figure 1 identification and certification label Approval Code Definition see Directive 2014 34 EU for further details II Non mining electrical equipment group for potentially explosive atmos...

Page 8: ...le for Use in hazardous areas other than mines ATEX group II equipment category 2 Use in zone 1 and 2 gas and 21 and 22 dust hazardous areas of explosive atmospheres Operating at temperature from 10 C...

Page 9: ...e gas That small current is then measured and converted by the 4 20 mA transmitter of the DAT 420 The sensing head of the DAT 420 consists of A flameproof d sensor housing base body top A sintered met...

Page 10: ...www dalemans com 10 2 3 Dimensions Figure 4 DAT 420 dimensions in mm...

Page 11: ...t be taken into account Consider the combination of sources of gas release with propagation effects The detector should be protected against operational hazards of the plant The detector should be pro...

Page 12: ...s below Attach the detector using suitable screws and plugs Always use the original wall mounting bracket supplied with the detector The sensing head should never be installed pointing upwards Ensure...

Page 13: ...DALEMANS recommend using colour coded cable with solid wires Use a shielded or a screened twisted pair cable The acceptable cross sectional area of the cable is 0 5 mm The maximum cable length should...

Page 14: ...Loosen the cable gland cap nut insert the cable into the cable gland and tighten Connect the wires to the 2 position terminal block according to the diagram below The cable wires must be stripped and...

Page 15: ...e Loop resistance The supply voltage applied to the detector has direct influence on the MAXIMUM loop resistance This resistance includes the cable resistance and the shunt resistor of the PLC Example...

Page 16: ...rminal connection does not exceed 1 mm distance Equipotential bonding may be provided using either the internal or the external connection For the external connection the bonding conductor should be a...

Page 17: ...nscrew the sensing head top using the suitable tool OUT00000113 Replace the sinter metal filter with a new one MEC00000010 Screw the sensing head top back on again and tighten Make sure the sensing he...

Page 18: ...t number Cable gland Ex d M20 6 1 11 7 mm PRE00000032 Ferrite FER00000001 Junction box Ex d BOI00000188 Key for locking screw 1 5 mm hex key OUT00000115 O ring 17 x 2 mm MEC00000012 Screw Locking scre...

Page 19: ...n sulphide H2S 50 ppm Nitrogen dioxide NO2 20 50 ppm Oxygen O2 25 Sulphur dioxide SO2 20 ppm Operating temperature 10 C to 40 C Storage temperature 40 C to 80 C Ambient humidity 20 90 HR Intermittent...

Page 20: ...Rue Jules M lotte 27 B 4350 Remicourt Tel 32 0 19 33 99 43 Fax 32 0 19 33 99 44 sales dalemans com OFFICIAL DEALER...

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