Evikon PluraSens E2618-LEL User manual

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PluraSens®
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Combustible Gas Transmitter
E2618-LEL
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User Manual
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E2618-LEL Rev 08.12.2020
Table of contents
Acetylene 4
Butane 5
Hydrogen 6
Methane 7
Propane 8
Specifications 9
Product description 11
Safety requirements 11
Operating conditions 11
Installation guidelines 12
Wall mount version 12
Duct mount version 12
Mounting dimensions 13
Sensor probe handling 14
Gas sensor replacement procedures 14
Operation 16
Maintenance 16
Calibration 16
Delivery set 17
Order code for E2618-LEL options 17
Configuring 18
Return to default settings 18
Modbus RTU Communication 19
RS485 communication interface 19
Communication parameters 19
Modbus holding registers 19
2

E2618-LEL Rev 08.12.2020
Warranty 23
Manufacturer contacts 23
 
3

E2618-LEL Rev 08.12.2020
Acetylene
A colorless flammable gas, lighter than air. Mixtures with air are explosive. It results from              
the interaction of calcium carbide with water. In industrial production, acetylene is mainly            
manufactured by the pyrolysis of light hydrocarbons.
Acetylene is widely used for welding and cutting of metals. The usage of acetylene as a               
feedstock in the chemical industry declines due to cost and environmental considerations.
Synonyms/Trade Names: Ethine, Ethyne.
 
4
Chemical formula
HC≡CH
Molar weight
26
Relative gas density (to air)
0.90
Conversion
1 ppm = 1.06 mg/m3
Boiling point
-84 °C
Low explosive limit (LEL), % vol. in air
2.3* (2.5**)
Upper explosive limit (UEL), % vol. in air
100
Odor
Odorless or with a faint ethereal smell if pure. The
commercial-grade may have a garlic-like smell due to
impurities.
Hazards
Highly flammable.
Gas/air mixtures are explosive. Forms explosive
acetylide compounds with copper, mercury, silver &
brasses (containing more than 66% copper).
Asphyxiant. Non-toxic, but, when generated from calcium
carbide, it can contain toxic impurities such as traces of
phosphine and arsine.
Exposure limits 
(NIOSH)
REL C
2662 mg/m3 /2500 ppm

E2618-LEL Rev 08.12.2020
Butane
A colorless flammable gas that is heavier than air. The term “butane” is used for any of two                 
structural isomers (n-butane or iso-butane, with unbranched and branched-chain        
respectively) or for their mixture. Occurs in light petroleum fractions.
Butane is used mainly as a fuel and as a feedstock in organic synthesis. It is applied also                 
as a propellant in aerosol sprays and may be used as an ozone-friendly refrigerant.
Mixtures of butane with propane and other hydrocarbons are referred to as LPG (liquefied             
petroleum gas).

 
5
Chemical formula
n-butane
CH3CH2CH2CH3
iso-butane
CH3CH(CH3)CH3
Molar weight
58
Relative gas density (to air)
2.0
Conversion
1 ppm = 2.38 mg/m3
Boiling point
-0.56 °C
−11.7 °C
Low explosive limit (LEL), % vol. in air
1.4* (1.6**)
1.5* (1.8**)
Upper explosive limit (UEL), % vol. in air
8.4
9.6
Odor
Gasoline-like odor
Hazards
Highly flammable.
Inhalation of butane can cause euphoria, drowsiness,
narcosis, asphyxia, cardiac arrhythmia, fluctuations in
blood pressure, and temporary memory loss, when
abused directly from a highly pressurized container, and
can result in death from asphyxiation and ventricular
fibrillation.
Exposure limits 
(NIOSH)
TWA
1900 mg/m3 /800 ppm
Not established

E2618-LEL Rev 08.12.2020
Hydrogen
A colorless, odorless, flammable gas, that is much lighter than air. Mixtures with air are              
explosive. Results from the interaction of acids, bases, and water with active metals and             
from the electrolysis of aqueous solutions. In industrial production, the main source of            
hydrogen is hydrocarbons.
 
6
Chemical formula
H2
Molar weight
2
Relative gas density (to air)
0.07
Conversion
1 ppm = 0.0818 mg/m3
Boiling point
−252.88 °C
Low explosive limit (LEL), % vol. in air
4.0
Upper explosive limit (UEL), % vol. in air
75
Odor
Odorless
Hazards
Flammable forms explosive mixtures with air.
Asphyxiant.
Exposure limits
not established

E2618-LEL Rev 08.12.2020
Methane
A colorless flammable gas, the main component of natural gas, marsh gases. Methane            
results from bacterial decomposition of plant and animal matter (landfill gas).
Methane is widely used as a fuel and chemical feedstock.
Synonyms: Marsh Gas, Natural Gas, Carbon tetrahydride, Hydrogen carbide.
 
7
Chemical formula
CH4
Molar weight
16
Relative gas density (to air)
0.55
Conversion
1 ppm = 0.65 mg/m3
Boiling point
−161.49 °C
Low explosive limit (LEL), % vol. in air
4.4* (5.0**)
Upper explosive limit (UEL), % vol. in air
15
Odor
Odorless when pure. Methane used in the kitchens
contains an odorant
Hazards
Highly flammable, mixtures with air are explosive.
Asphyxiant.
Exposure limits
not established

E2618-LEL Rev 08.12.2020
Propane
A colorless flammable gas that is heavier than air. it occurs in light petroleum fractions.
Propane is used mainly as a fuel and as a feedstock in organic synthesis. It is applied also                 
as a propellant in aerosol sprays and may be used as an ozone-friendly refrigerant.
Mixtures of propane with butane and other hydrocarbons are referred to as LPG (liquefied             
petroleum gas).

Conversion of ppm to mg/m3 is calculated for 25°C and 1 atm.
* according to new EU standards ('stirred' concentration of gas)
** according to US standard (‘still gas’ method)
 
8
Chemical formula
CH8CH2CH8
Molar weight
44
Relative gas density (to air)
1.55
Conversion
1 ppm =1.80 mg/m3
Boiling point
−42 °C
Low explosive limit (LEL), % vol. in air
1.7* (2.1**)
Upper explosive limit (UEL), % vol. in air
9.5
Odor
Odorless when pure. Commercially available propane for
fuel purposes may contain odorant (“gas smell”).
Hazards
Highly flammable, mixtures with air are explosive.
Asphyxiant. May cause dizziness, confusion, excitation
when inhaled.
Exposure limits 
(NIOSH)
TWA
1800 mg/m3 /1000 ppm
IDLH
2100 ppm [10%LEL]

E2618-LEL Rev 08.12.2020
Specifications
9
Detected gases
Acetylene, Butane, Hydrogen, Methane, Propane, etc
Sampling method
Diffusion
Sensor type
Metal oxide semiconductor
Catalytic (pellistor)
Typical detection range
0...100% LEL
0...100% LEL
Resolution / digital unit
0.1% LEL
1% LEL
Response time T90
ca. 60 s
8 s
Sensor lifetime
> 5 years
> 2 years
Calibration interval
12 months
3...6 months
Operating conditions
-30...+70 °C
-20 to +60°C
<95% RH non-condensing, 0,9...1,1 atm, Explosion-safe indoor areas,
Normal ambient oxygen level
Avoid strong mechanical shock, vibrations, or EMI
Avoid exposure to corrosive gases or silicone-containing products
NOTE! Transmitter with a catalytic type sensor is not suitable for acetylene
detection
Signal update
Every 1 second
Power supply options
11...30 VDC or 24 VAC
Power consumption
< 2 VA
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
Analog outputs
2 × 4-20 mA / 0-10 V, user settable
Outputs assignment
OUT1 2 gas; OUT2 2 gas
Output scale width
> 10 × resolution
Recommended: 20-100% of the detection range
Cable connections
Screwless spring-loaded terminals
Enclosure
Grey ABS, wall mount, protection class IP65
Dimensions
H82 × W80 × D55 mm
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

E2618-LEL Rev 08.12.2020
10
Other options
Remote probe
Protection IP65, default cable length 3.0 m;
max height 80 mm, max diameter 65 mm

E2618-LEL Rev 08.12.2020
Product description
E2618 series 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.
E2618 series provide two independent analog outputs OUT1 and OUT2, user-selectable to           
4-20 mA or 0-10 V, proportional to the chosen scale for gas concentration. RS485 Modbus              
RTU digital communication interface allows easy instrument configuration and integration         
into various automation systems.
Remote probe and duct mount versions are available.
The version of your transmitter is marked on the package. If the ⚠ symbol is marked on                
the product, 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.
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.

11

E2618-LEL Rev 08.12.2020
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 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.),
●For gases lighter than air install the sensor higher than the potential           
leakage/generation source or near the ceiling. Combustible gases lighter than air          
are hydrogen, methane, and acetylene. Propane and butane are heavier than air           
and tend to sink. It is recommended to place the sensor lower than potential             
leakage or generation 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 transmitters should be           
distributed evenly in the room.
For personal safety control, the transmitters are installed in the breathing zone (at the             
height of the head of people or animals). The recommended sensor position is vertical,             
pointing downwards.
Wall mount version
Unscrew four lid screws and detach the lid from the transmitter. Attach the device to a wall                
with screws passing through mounting holes (for dimensions see the drawing in the next             
section).
Duct mount version
Cut a hole with a diameter of 36...45 mm in the air duct at the chosen mounting place.                 
Place the rubber flange aligning the holes in the flange and the air-duct and fix the flange                
with four self-tapping screws. Pass the sensor probe through the flange and adjust it to the               
appropriate depth. Unscrew four lid screws and detach the lid from the transmitter.
12

E2618-LEL Rev 08.12.2020
Mounting dimensions

Wall mount version

Duct mount version
13

E2618-LEL Rev 08.12.2020
Sensor probe handling
The wall mount version of the transmitter is available with a remote probe (see drawing              
below for dimensions). The remote probe is connected to the main unit with a shielded              
cable. The default connection cable length is 3 m.

A)Wall mount remote probe with fixing clamp (default version),
B)Remote probe with rubber flange and three self-tapping screws (on request)

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 M25 nut and remove the old              
filter. Place a new filter into the nut 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.
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 pellistor (catalytic) sensor from the device,
5. Insert the new pellistor (catalytic) sensor inside,
6. Put back the O-ring rubber, PTFE filter, and the head cap, respectively.
NOTE! Metal oxide semiconductor sensors are not replaceable!
14

E2618-LEL Rev 08.12.2020
Electrical connections
Unscrew four lid screws and detach the lid from the device. Use the M16 cable gland to let                 
in cables of the power supply and of the external devices. Attach the power cable to the                
device without turning it on. Using the connection diagram below, connect the analog            
outputs and digital interface terminals to the relevant devices according to your tasks.


PCB without PSU and relays
The screwless quick connect spring terminals on the E2618 series devices are suitable for             
a wide range of wires with a cross-section of 0.2...1.5 mm2. We recommend to strip the               
wire end by 8...9 mm and use wire end sleeves.
To connect the wire, insert the wire end into the terminal hole. To disconnect, push the               
spring-loaded terminal lever, pull the wire out, and release the lever.
Use a twisted-pair cable, e.g. LiYY TP 2×2×0.5 mm2or CAT 5, to connect the device to the                 
RS485 network. A and B on the device represent data+ and data- respectively, polarity must              
be respected when connecting to an external RS485 network. 
Both analog outputs can be independently changed between 4-20 mA and 0-10 V type             
using jumpers J1 (OUT1) and J2 (OUT2). By closing pins on a specific jumper the related               
output is 0-10 V, with an open jumper the output is 4-20 mA. Power restart is required after                 
changing the position of the jumpers.
 
15

E2618-LEL Rev 08.12.2020
Operation
Turn on the power. The instrument warm-up time takes about 1 minute after switching on              
and the final sensor stabilization time to maximum accuracy takes about 1 hour. The             
operating status is indicated by the LED on the PCB of the device. The control LED (red)                
response to different processes is presented in the following table:

Make sure that the transmitter is properly mounted, the external devices connected, power            
LED (green) on and control LED is constantly lit. Place the lid back and fix it with the                 
screws. The device is ready to use.
Maintenance
Do not perform any maintenance operation with the power on.
Clean the device with a soft damp cloth. Do not use any abrasive cleaning agents. Do not                
immerse the device in water or any cleaning media.
Calibration
E2618-LEL gas transmitters have been calibrated by the Manufacturer with standard gas           
mixtures before delivery. Provided that the sensor is used under moderate conditions, the            
recommended interval for field recalibration is 12 months for the MOS sensor and 3-6             
months for the catalytic sensor. Please contact your dealer for more information.

16
Mode
LED mode
During calibration mode or sensor heating
period (if activated)
0.5 Hz (50% on, 50% off)
During Modbus communication cycle
Short on-off pulses
Normal operating/measurement
Continuously on or off

E2618-LEL Rev 08.12.2020
Delivery set
●Gas transmitter E2618 (wall mount, duct mount, or remote probe version)
●Mounting accessories:
○4 screws with plastic dowels for wall mount version
○Square Rubber flange for Duct mount option
○Round rubber flange for Remote probe option
○Fixing clamp for Remote probe option


Order code for E2618-LEL options


17
E2618 options
Order code
Remote probe, 3 m cable
E2618-LEL-RP33-3
Remote probe, 10 m cable
E2618-LEL-RP33-10
Duct mount option, stem Ø35×L230 mm
E2618-LEL-DM
Integrated 24 VAC power supply module 
E2618-LEL-24VAC
Remote LCD single value display, wall mount box
115 × 65 × 40mm, 3 m cable
E2618-LEL-RLCD3

E2618-LEL Rev 08.12.2020
Configuring
A standard configuration kit includes a USB-RS485 converter, fixed flow regulator, gas           
tubing with applicators, and a software pack. Please contact your Seller for more            
information.
Gas transmitters E2618 share all functionalities of the PluraSens®multifunctional         
transmitter platform. The features and options include:
●Digital output change rate-limiting filter
●Digital integrating (averaging) filter
●Free assignment of each analog output to the chosen parameter
●Flexible setting of analog output scales for each output
●Output zero and slope adjustment for calibration

The output scales can be changed by Modbus commands by using the configuration            
software and the standard kit (see Modbus RTU Communication).
Return to default settings
To reset the device’s Slave ID, baud rate, and stop bit numbers to factory settings, proceed               
as follows:
1. De-energize the device 
2. Connect the X6 jumper
3. Turn on the device 
4. De-energize the device
5. Disconnect the X6 jumper 
6. Turn on the device
 
18

E2618-LEL Rev 08.12.2020
Modbus RTU Communication
RS485 communication interface

Communication parameters
Modbus holding registers
Register addresses are shown 0-based, Addr in hexadecimal, Reg in decimal format.
Modbus holding register numbers MHR are shown in the decimal 1-based format and may             
be addressed either from 00001 or 40001 base.
19
Databits: 8 
Parity: none / odd / even 
Stop bits: 1 or 2 
Protocol: Modbus RTU
Supported Modbus functions:
03 – Read multiple registers
06 – Write a single register
Parameter
Permitted values
Default
Supported baud rates
1200, 2400, 4800, 9600, 19200, 38400, 57600
9600
Data bits
8
8
Parity
none / odd / even
none
Stop bits
1, 2
1
Protocol
Modbus RTU

Modbus functions
03 - Read multiple registers
06 - Write a single register
Error codes
01 – Illegal function
02 – Illegal data address
03 – Illegal data value
04 – Slave device failure
(details of last error 04 can be read from register 0x0008)
Addr
Reg / MHR
RW
Description
Supported values (dec)
Default
0x0001
1 / 40002
R
Hardware version

-
0x0002
2 / 40003
R
Software version

-
0x0003
3 / 40004
R
Product serial number
1...65535
-
0x0004
4 / 40005
RW
Slave ID (net address) *
1...247 **
1
0x0005
5 / 40006
RW
Baud rate *
1200, 2400, 4800, 9600, 19200,
38400, 57600
9600

E2618-LEL Rev 08.12.2020

20
0x0006
6 / 40007
RW
Response delay, ms
1...255
10
0x0007
7 / 40008
RW
Stop bits, parity bit *
1 – No parity bit, 1 stop bit
(default after factory reset)
2 – No parity bit, 2 stop bits
3 – Odd parity, 1 stop bit
4 – Even parity, 1 stop bit
NOTE: 3 and 4 are available
starting from the Software
version 0x218 (dec. 536)
1
0x0008
8 /40009
R
Last error code
1...255
-
0x0011
17 / 40018
RW
Technological:
age of last data in seconds
(read) / restart (write)
0...65535 s (read),
writing 42330 restarts the
instrument
-
0x00A5
165 / 40166
RW
Zero adjustments for gas
data, ADC
-32000...+32000 ADC units
0
0x00A6
166 / 40167
RW
Slope adjustment for gas
data
1...65535
512
0x00A7
167 / 40168
RW
Change rate limit for gas
data, ppm (‰ for O2) / s
1...32000, 0 - no limit
0
0x00A8
168 / 40169
RW
Integrating filter time
constant, s
1...32000 (seconds),
0 - no filter
0
Addr
Reg / MHR
RW
Description
Supported values (dec)
Default
0x00C9
201 / 40202
RW
Parameter tied to analog
output 1
0 – None
2 – Gas concentration
9 – Forced Modbus control, 
value set in MHR / 40204
2
0x00CA
202 / 40203
RW
Parameter tied to analog
output 2
0 – None
2 – Gas concentration
9 – Forced Modbus control,
value set in MHR / 40205
2
0x00CB
203 / 40204
RW
Forced value for analog
output 1***
0...1000
(0.0%...100.0% of output scale)
0
0x00CC
204 / 40205
RW
Forced value for analog
output 2***
0...1000
(0.0%...100.0% of output scale)
0