Evikon PluraSens E2638 Series User manual

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PluraSens®
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Hydrogen Sulfide Detector-Transmitter
E2638-H2S
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User Manual
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E2638-H2S Rev 10.03.2021
Table of contents
Hydrogen Sulfide 3
Specifications 4
Product description 6
Safety requirements 6
Operating conditions 7
Installation guidelines 7
Mounting dimensions 8
Sensor probe handling 9
Gas sensor replacement procedures 9
Electrical connections 10
Operation 12
Maintenance 12
Calibration 12
Delivery set 13
Order code for E2638-H2S options 13
Configuring 14
Return to default settings 14
Modbus RTU Communication 15
RS485 communication interface 15
Communication parameters 15
Modbus holding registers 15
Warranty 20
Manufacturer contacts 20
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2

E2638-H2S Rev 10.03.2021
Hydrogen Sulfide
Colorless toxic, corrosive and flammable gas with a smell of rotten eggs. Occurs in natural              
gas, volcanic gases, petroleum, and some sources of well water. It results from the             
anaerobic decay of sulfur-containing proteins, e.g. in sewers.
Synonyms: Hydrosulfuric acid, Sewer gas, Sulfuretted hydrogen.
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Conversion of ppm to mg/m3 is calculated for 25°C and 1 atm.
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3
Chemical formula
H2S
Molar weight
34
Conversion
1 ppm = 1.40 mg/m3
Relative gas density (to air)
1.17
Boiling point
−60 °C
Low explosive limit (LEL), % vol. in air
4.0
Upper explosive limit (UEL), % vol. in air
44.0
Odor
The characteristic smell of rotten eggs. Above 30 ppm,
the odor is described as sweet or sickeningly sweet.
Odor threshold
0.01-1.5 ppm
Note: Sense of smell becomes rapidly fatigued and can
NOT be relied upon to warn of the continuous presence of
H2S.
Hazards
Highly flammable, explosive gas.
Broad-spectrum poison, mostly affecting the nervous
system. At low concentrations causes eye irritation, a
sore throat and cough, nausea, shortness of breath, and
pulmonary edema. Long-term, low-level exposure results
in fatigue, loss of appetite, headache, poor memory,
irritability, and dizziness. Exposure to high levels can
induce immediate collapse, with loss of breathing and a
high probability of death.
Exposure limits 
(Commission
Directive
2009/161/EU)
TWA
7 mg/mm3 / 5 ppm
STEL
14 mg/mm3 / 10 ppm
IDLH (NIOSH)
140 mg/mm3 / 100 ppm

E2638-H2S Rev 10.03.2021
Specifications
4
Sensor type
Electrochemical cell
Sampling method
Diffusion
Typical detection range
0...100 ppm
0...2000 ppm
Maximum overload
500 ppm
4000 ppm
Resolution / digital unit
0.1 ppm
1 ppm
Response time T90
< 30 s
< 25 s
Operating temperature
-30...+50 °C
-40...+50 °C
Sensor lifetime
> 2 years
Calibration interval
6 months
Signal update
Every 1 second
Power supply
11...30 VDC,
24 VAC or 90...265 VAC as options
Power consumption
< 2 VA
Analog outputs
2 × 4-20 mA / 0-10 V, user settable
Load resistance
RL < (Us - 2 V) / 22 mA for 4-20 mA
RL > 250 kOhm for 0-10 V mode
Digital interface
RS485, Modbus RTU protocol; No galvanic isolation
Enclosure
Grey ABS, wall mount, protection class IP65
Dimensions
H90 × W145 × D55 mm
(overall dimensions H140 × W145 × D55 mm)
Outputs assignment
OUT1 gas; OUT2 gas
NOTE! for the LCD version only output 1 is available
Output scale width
> 10 × resolution
Recommended: 20-100% of the detection range
CE marking
According to 2014/30/EU and 2014/35/EU, EN 50491-4-1:2012
EN 61000-6-3:2020, EN 61326-1:2013(EMC, emissions)
EN 61000-6-1:2019, EN 61000-6-2:2019(EMC, Immunity)
EN 60079-29-1:2016, EN 60079-29-2:2015 and EN 60079-29-3:2014
Operating conditions
(operating temperature is specified above)
15...90% RH Non-condensing, 0,9...1,1 atm
Explosion-safe areas,
Non-aggressive atmosphere

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Relay option
Output relays
2 × SPST relays (closing contact),
250 VAC / 30 VDC, 5 A max
Default alarm setpoints
(set/release)
LOW: 10 ppm/ 8 ppm
HIGH: 20ppm/16 ppm
Determined by user
within 5-95% of the range
Signaling options
Visual
Red and green LEDs
Acoustic alarm
Buzzer 85 dB
LCD indicator option
Operating temperature
0...+50 °C
Display dimensions
72 × 36 mm
Number of digits
3.5 7-segment
Character height
14 mm
Other features
backlight
Other options
Remote probe
Protection IP65, default cable length 3.0 m;
max height 80 mm, max diameter 65 mm

E2638-H2S Rev 10.03.2021
Product description
E2638 series detectors-transmitters belong to the PluraSens® family of multifunctional         
measurement instruments. The instruments utilize gas sensors of various types with          
excellent repeatability, stability, and long lifetime.
E2638 series provides two independent analog outputs OUT1 and OUT2, user-selectable to           
4-20 mA or 0-10 V, proportional to gas concentrations. RS485 Modbus RTU digital            
communication interface allows easy instrument configuration and integration into various         
automation systems.
The following features are available as an option:
●Two relays RE1 and RE2 with closing contacts. Relay outputs can be used to             
switch alarm sirens, ventilation fans, shut-off valves, or other actuators,
●Acoustic (85 dB buzzer) and visual (red and green LED) signaling,
●24 VAC or 230 VAC as options for power supply module,
●LCD indicator,
●Remote probe.
The version of your device is marked on the package. If the symbol ⚠ is marked on the                 
equipment, consult the documentation for further information.
Safety requirements
Misuse will impair the protection of the product. Always adhere to the safety provisions             
applicable in the country of use.
Do not perform any maintenance operation with the power on. Do not let water or foreign               
objects inside the device.
Removal of the PCB from the enclosure voids the warranty. Do not touch the electronic              
components directly, as they are sensitive to static electricity.
Connection diagrams can be found in the electrical connections section. The device might            
not perform correctly or be damaged if the wrong power supply is connected.
External circuits connected to the equipment should have sufficient insulation rating          
according to the environmental conditions and equipment power.
A disconnecting device that is marked as such and easily accessible should be included in              
the installation of this product.
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E2638-H2S Rev 10.03.2021
Operating conditions
The device should be used both in a non-hazardous area and in a basic electromagnetic              
environment, where the latter is defined in EN 61326-1. Avoid strong mechanical shock and             
vibrations. Avoid corrosive atmosphere and areas highly contaminated with dust, oil mist,           
etc. Keep the instrument away from direct sunlight. A sudden temperature or humidity            
change might affect the sensitivity of the sensor.
Installation guidelines
Before proceeding with the installation it is mandatory to read the Safety requirements            
section and make sure to comply with all listed instructions. Installation standards EN            
60079-29-2 and EN 45544-4 are also recommended for further instructions and related           
information about the installation. During the installation of the detector-transmitter the          
following points must be considered:
●Application (air quality control or leakage detection)
●Properties of the space under investigation (room geometry, direction, and         
velocity of airflows, etc.),
●Hydrogen sulfide is slightly heavier than air and spreads evenly in the room. The             
recommended location is close to the potential leakage source.
●The device should be accessible for maintenance and repair.
The aforementioned conditions above will affect the coverage area of the device. however,            
the coverage area for a transmitter is usually between 2.5 to 5 meters radius.
For early leakage detection install the sensor as close as possible to the potential leakage              
sources (flanges, valves, pressure reducers, pumps, etc.), taking into consideration other          
points listed above.
For general area monitoring without definite leakage sources, the detectors should be           
distributed evenly in the room.
For personal safety control, the detectors are installed in the breathing zone (at the height              
of the head of people or animals). The recommended sensor position is vertical, pointing             
downwards.
For installing the device, attach the device to the wall using provided screws through the              
side mounting holes or key slots (see mountains dimensions).
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E2638-H2S Rev 10.03.2021
Mounting dimensions
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Front view
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Bottom view
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E2638-H2S Rev 10.03.2021
Sensor probe handling
The E2638 series devices are available with a remote probe. The remote probe is             
connected to the main unit with a shielded cable. The default remote probe cable length is               
3 m.
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A) Wall mount remote probe with fixing clamp (default version),
B) Remote probe with rubber flange and three self-tapping screws (on request)
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The sensor probes of all types are equipped with a hydrophobic microporous PTFE filter to              
protect the sensor from dust, dirt, and water drops. The filter should be replaced if it gets                
strongly contaminated. To replace the PTFE filter, unscrew the sensor head cap and            
remove the old filter. Place a new filter into the cap and tighten it again.
NOTE! Never stab or press the filter near its center where the sensor is located since this                
may damage the sensor. Do not remove the filter as it may cause the device to show                
incorrect values and/or break the sensor.
The recommended orientation of the sensor probe is vertical with the sensor tip pointing             
downwards. This prevents the possible accumulation of condensed water on the sensor           
protection filter.
Gas sensor replacement procedures
1. Remove the sensor head cap from the device (or the remote probe),
2. Remove the PTFE filter (if it is not removed within the cap),
3. Remove the O-ring rubber,
4. Detach the electrochemical sensor from the device,
5. Insert the new electrochemical sensor inside,
6. Put back the O-ring rubber, PTFE filter, and the head cap, respectively.
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E2638-H2S Rev 10.03.2021
Electrical connections
Unscrew four lid screws and detach the lid from the device. Use two M16 cable glands to                
let in the cables of the power supply and of the external devices. Without turning on the                
power, plug the power cable, and connect the analog/relay outputs and/or digital interface            
terminals to the necessary devices according to the relevant connection diagram.
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Version with PSU and relays Version with PSU and without relays
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Version without PSU and with relays Version without PSU and relays
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10