GHM Delta OHM PMsense-M User manual

Operating manual
PM / CO2Transmitter
PMsense
www.deltaohm.com
English
Keep for future reference.
Companies / Brands of
GHM

PMsense - 2 - V1.0
TABLE OF CONTENTS
1 INTRODUCTION ........................................................................................ 3
2 TECHNICAL SPECIFICATIONS ...................................................................
3 INSTALLATION ......................................................................................... 5
3.1 E LECTRIC L CONNECTIONS .......................................................................... 5
CONFIGURATION AND MEASUREMENT ..................................................... 8
5 PROPRIETARY PROTOCOL ........................................................................ 9
6 MODBUS-RTU PROTOCOL ........................................................................ 15
7 SAFETY INSTRUCTIONS .......................................................................... 20
8 ORDERING CODES .................................................................................. 21

PMsense - 3 - V1.0
1 INTRODUCTION
PMsense is a PM1.0, PM2.5 and PM10 Particulate Matter transmitter suitable for
outdoor air quality monitoring.
The dust particles concentration is measured using the laser scattering principle.
n optional CO
2
sensor can be integrated in the transmitter.
The transmitter has a digital RS485 output with MODBUS-RTU or SCII proprietary
protocol. version with two additional 4…20 m (0…10 V on request when ordering)
analog outputs is available. The two analog outputs can be independently associated
with any of the measured parameters.
The measuring circuit of the transmitter can be operated in continuous mode or, in
order to extend the PM sensor lifetime, at cyclic intervals (default operating mode).
The measuring cycle interval is user configurable.
The transmitter is maintenance-free and has fast response, high sensitivity, excellent
stability and long operating life.

PMsense - 4 - V1.0
2TECHNICAL SPECIFICATIONS
Particulate Matter
Measuring principle Laser scattering
Measured pollutants PM1.0, PM2.5 and PM10
Measuring range 0…1000 µg/m
3
(for each pollutant)
Particle size detection range ∅ 0.3…10 µm
Linearity error < 5%
Repeatability < 3%
Sensor warm up time 15 s
Sensor lifetime 5 years approx. in 5 minutes cyclic operating mode (default)
> 10,000 hours in continuous operating mode (1 meas./s)
Temperature drift < 0.01 µg/m
3
/°C
CO
2
(only PMBsense…)
Measuring principle Double wavelength NDIR
Measuring range 0…5000 ppm
ccuracy ±(50 ppm+3% of measurement) @ 25 °C and 1013 hPa
Response time < 120 s (air speed= 2 m/s)
Long-term stability 5% of measurement / 5 years
Temperature drift 1 ppm/°C
General specifications
Output RS485 with Modbus-RTU or SCII proprietary protocol
Only PMsense-A: 2 x analog 4…20 m (R
Lmax
= 500 Ω); on
request 2 x 0…10 V (R
Lmin
= 10 kΩ)
Power supply 7…30 Vdc
(15…30 Vdc for 0…10 V analog outputs)
Power consumption 25 m @ 24 Vdc during measurement
4 m in stand-by (only for cyclic operating mode)
The indicated consumption does not include the consumption
due to the analog outputs
Connection M12 8-pole circular connector
Operating conditions -20…+70 °C / 0…95 %RH / 500…1500 hPa
Housing material Polycarbonate
Protection degree Housing equipped with a rain-proof and UV resistant inlet air
filter – IP 53
Dimensions 120 x 94 x 71 (excluding M12 connector)
Weight 330 g

PMsense - 5 - V1.0
3INSTALLATION
The transmitter is equipped with a bracket with U-bolt for the fixing to a Ø40…50 mm
mast. It can be fixed to a wall using the bracket only, by removing the U-bolt.
Fig. 3.1: transmitter description
3.1 E LECTRICAL CONNECTIONS
The transmitter has a M12 8-pole circular connector and uses the CPM12-8DA... op-
tional cables, with M12 8-pole connector on one side and open wires on the other side.
12
3
456
7
81 2
3
4
5
6
78
Fig. 3.2: connectors pinout
Transmitter male
connector
(external view)
Connector
Fixing b
racket with
U
-
bolt
ir outlet
ir inlet
Cable female connector
(external view)
Connector reference

PMsense - 6 - V1.0
Connector
pin N° Function CPM12-8DA… wire color
1 Power supply negative (GND) Blue
2 Power supply positive (+Vdc) Red
3 Not used ---
4 RS485 /- Brown
5 RS485 B/+ White
6 Digital and analog outputs ground (SGND)* Grey
7 nalog output 1 positve ( OUT1, only PM[B]sense-A) Yellow
8 nalog output 2 positve ( OUT2, only PM[B]sense-A) Green
Cable shield ** Black (thick wire)
* The output ground (SGND) and the negative of the power supply (GND) are short-circuited
inside the transmitter.
* The cable shield is not connected to the M12 connector.
To ensure a good noise immunity, it is recommended to connect the cable shield to
ground (GND).
RS 85 connection:
By default, the instrument has MODBUS address 1 and communication parameters
19200, 8E1. Different parameters can be set using the proprietary protocol or the
MODBUS-RTU protocol.
220Ω
220Ω ShieldShield
Lmax = 1200m
B/+
A/-
B/+
A/-
SGND
GND
+Vdc
B/+
A/-
SGND
+
-
Fig. 3.3: RS 85 connection
Power supply
7…30 Vdc
CPM12-8D … cable
PLC, data logger or
RS485/USB or RS485/RS232
converter for PC
Other sensors with
RS485 output
Termination Termination

PMsense - 7 - V1.0
Current analog output (only PM[B]sense-A):
By default, the current analog outputs are 4…20 m , with:
4 m = 0 ppm
20 m = 1000 µg/m
3
The analog output 1 is associated by default to PM2.5. The analog output 2 is associ-
ated by default to PM10.
With the commands of the proprietary protocol it is possible to associate the analog
outputs to different parameters, set the range 0…20 m for the output and reverse the
direction of the output, so that the output decreases as the measurement increases.
In case of measurement error, the output goes to 22 m .
I
0/4...20 mA
OUT1
+
-
RL
I
0/4...20 mA
OUT2
+
-
RL
SGND
AOUT1
GND
+Vdc +
-
AOUT2
Fig. 3. : current analog outputs connection
Voltage analog output (optional, only PM[B]sense-A):
By default, the voltage analog outputs are 0…10 V, with:
0 V = 0 ppm
10 V = 1000 µg/m
3
The analog output 1 is associated by default to PM2.5. The analog output 2 is associ-
ated by default to PM10.
With the commands of the proprietary protocol it is possible to associate the analog
outputs to different parameters, set the range 2…10 V for the output and reverse the
direction of the output, so that the output decreases as the measurement increases.
In case of measurement error, the output goes to 11 V.
+
-
RL
+
-
RL
SGND
AOUT1
V
0...10 V
OUT1 V
0...10 V
OUT2
GND
+Vdc
+
-
AOUT2
Fig. 3.5: voltage analog outputs connection
Power supply 12…30 Vdc
R
Lmax
= 500 Ω
CPM12-8D … cable
Power supply 15…30 Vdc
CPM12-8D … cable
R
Lmin
= 10 kΩ

PMsense - 8 - V1.0
CONFIGURATION AND MEASUREMENT
The configuration of the instrument and the reading of the measurements can be done
via the RS485 serial output, both with the proprietary protocol and with the MODBUS-
RTU protocol.
In the first 10 seconds after the instrument power on, it is always active the proprie-
tary protocol. fter 10 seconds from power on, the operating protocol is activated,
which by default is the MODBUS-RTU protocol.
It is possible to keep the proprietary protocol active even after 10 seconds from power on
by sending, before the 10 seconds expire, the command @ of the proprietary protocol.
The proprietary protocol can be set as operating protocol by means of the DP0 command.
The commands of the proprietary protocol and the registers of the MODBUS-RTU pro-
tocol are described in detail in the following chapters.
Particulate Matter measurement modes:
The transmitter can perform the PM measurement in continuous mode, or, in order to
extend the sensor lifetime, at cyclic intervals.
By default, the transmitter is configured to measure at cyclic intervals with an interval
of 5 minutes. The measurement mode and the interval can be configured respectively
by using the CPLS and CPLP commands of the proprietary protocol or the holding reg-
isters with address 15 and 16 of the MODBUS-RTU protocol.
In the measurement mode at cyclic intervals, the PM sensor is activated periodically
for about a minute, at the end of which the measurement is made available and "fro-
zen" (the sensor is deactivated) until the set cyclic measurement interval expires. The
measurement provided is a value averaged during the minute of sensor activation.
In continuous measurement mode the sensor is always active, and the measurement
provided is an averaged value chosen from the following possibilities:
•average over a 10 seconds interval, updated every second;
•average over a 60 seconds interval, updated every 10 seconds (default);
•average over a 15 min interval, updated every minute.
The type of average can be configured by using the CPS command of the proprietary
protocol or the holding registers with address 19 of the MODBUS-RTU protocol.
Status of the transmitter:
There are two LEDs on the internal electronic board of the transmitter: the green LED
indicates the presence of the external power supply (blinks once per second), the red
LED indicates the presence of any measurement errors (normally off, it blinks twice
per second if at least one of the measured parameters is in error).

PMsense - 9 - V1.0
5PROPRIETARY PROTOCOL
To use the proprietary protocol, it is necessary to connect the instrument to the PC via
a RS485/USB (e.g. RS51K) or RS485/RS232 converter and use a standard serial
communication program. In the serial communication program, set the COM port
number to which the instrument is connected and the communication parameters as
follows:
•If the MODBUS-RTU protocol is set as the operating protocol in the instrument
(default), set the Baud Rate 57600 and the parameters 8N2 in the serial commu-
nication program, then power cycle the instrument and send the command @
within 10 seconds from the instrument power on.
•If the proprietary protocol is already set as the operating protocol in the instru-
ment, it is possible to operate with Baud Rate 57600 and parameters 8N2 by
sending the command @ within 10 seconds from the instrument power on, or
you can let the 10 seconds pass without sending the command @ and operate
with the communication parameters set in the instrument (default 19200, 8E1).
To change the instrument configuration, the serial command CAL USER ON must be
sent first (the instrument replies with USER C L MODE ON). The command C L USER ON
is automatically disabled after a few minutes of inactivity. If the settings should be only
read, the command C L USER ON is not required.
Below is the list of the serial commands.
Instrument information:
Command Reply Description
G0 Model Instrument model
G1 &Revision| Instrument hardware revision
G2 SN=nnnnnnnn Instrument serial number
G3 Firm.Ver.=x.y Instrument firmware revision
G4 Firm.Date=yyyy/mm/dd Date of firmware revision
GC Fact.Calib.Date= yyyy/mm/dd
User.Calib.Date= yyyy/mm/dd
Cal.Mode=Factory or User
Date of factory calibration
Date of user calibration (CO
2
only)
Type of calibration active (CO
2
only)
Protocol:
Command Reply Description
@ &| Keeps the proprietary protocol operational even after 10
seconds from instrument power on. It must be sent within
10 seconds from instrument power on.
DPn &| Sets the operating protocol:
Proprietary if n=0
MODBUS-RTU if n=1
Default : MODBUS-RTU (n=1)
RP & n| Reads the operating protocol set in the instrument.
SM &| ctivates the MODBUS-RTU protocol immediately.
CM n &| Sets the instrument address for the MODBUS-RTU pro-
tocol to n.
The address should range within 1 and 247.
Default : 1
RM & n| Reads the instrument address for the MODBUS-RTU pro-
tocol.

PMsense - 10 - V1.0
Note: after sending the DP1 command, the instrument remains with the proprietary protocol.
Send the command SM to activate the MODBUS-RTU protocol immediately, or power cycle the
instrument.
RS 85 communication parameters:
Command Reply Description
CMBn &| Sets the Baud Rate:
1200 if n=0
2400 if n=1
4800 if n=2
9600 if n=3
19200 if n=4
38400 if n=5
57600 if n=6
115200 if n=7
Default : 19200 (n=4)
RMB & n| Reads Baud Rate setting
CMPn &| Sets parity and stop bits:
8N1 if n=0 [No parity, 1 stop bit]
8N2 if n=1 [No parity, 2 stop bits]
8E1 if n=2 [Even parity, 1 stop bit]
8E2 if n=3 [Even parity, 2 stop bits]
8O1 if n=4 [Odd parity, 1 stop bit]
8O2 if n=5 [Odd parity, 2 stop bits]
The number of data bits is fixed to 8.
Default : 8E1 (n=2)
RMP & n| Reads the setting of parity and stop bits.
CMWn &| Sets waiting time after transmission with MODBUS-RTU
protocol:
Immediate reception if n=0 (violates protocol)
Waiting 3.5 characters if n=1 (respects protocol)
Default : Immediate reception (n=0)
RMW & n| Reads the setting of waiting time after transmission with
MODBUS-RTU protocol.
PM measurement settings:
Command Reply Description
CPLSn &| Sets the PM measurement mode:
Continuous if n=0
t cyclic intervals if n=1
Default : t cyclic intervals (n=1)
RPLS & n| Reads the setting of the PM measurement mode.
CPLPn &| Sets the cycle interval for the measurement mode at cy-
clic intervals.
The number of seconds must be greater than 70, in or-
der to allow the sensor to take the measurement.
Default : 300 (=5 min)
RPLP & n| Reads the setting of the cycle interval for the measure-
ment mode at cyclic intervals.

PMsense - 11 - V1.0
Command Reply Description
CPSn &| Sets the type of measurement averaging for the contin-
uous measurement mode:
verage over a 10 seconds interval, updated every
second if n=0
verage over a 60 seconds interval, updated every
10 seconds if n=1
verage over a 15 minutes interval, updated every
minute if n=2
Default : verage over a 60 seconds interval, updated
every 10 seconds (n=1)
RPS & n| Reads the type of measurement averaging for the con-
tinuous measurement mode.
Analog outputs (only PM[B]sense-A):
Command Reply Description
C 1On &| Enable/disable the offset of the analog output 1:
Offset disabled if n=0 (0…20 m or 0…10 V)
Offset enabled if n=1 (4…20 m or 2…10 V)
Default : Offset enabled (n=1) if the output is current,
offset disabled (n=0) if the output is voltage (optional)
R 1O & n| Reads the setting of the offset for the analog output 1.
C 1SOn &| Sets the direct or inverse correspondence between analog
output 1 and associated physical quantity:
4 m /0 V  Min. quantity, 20 m /10 V  Max.
quantity if n=0
20 m /10 V  Min. quantity, 4 m /0 V  Max.
quantity if n=1
Default : Direct correspondence (n=0)
R 1SO & n| Reads the type of correspondace (direct or inverse) be-
tween analog output 1 and associated physical quantity.
C 1Tn &| ssociates the analog output 1 to:
PM1.0 if n=0
PM2.5 if n=1
PM10 if n=2
CO
2
if n=12 (only PMBsense- )
Default : PM2.5 (n=1)
Note: the PM measurement is updated according to the op-
erating mode set with the CP S, CP P and CPS commands.
R 1T & n| Reads the physical quantity associated to analog output 1.
C 1Ln &| Sets n as the minimum value of the measuring range of
the physical quantity associated to the analog output 1.
If the output is associated to PM, the value must be ex-
pressed as a number of tenths (e.g. n=5 to indicate 0.5
µg/m
3
). If the output is associated to CO
2
, the value must
be expressed as a number of units (e.g. n=200 to indicate
200 ppm).
Default : 0
R 1L & n| Reads the minimum value of the measuring range of the
physical quantity associated to the analog output 1.

PMsense - 12 - V1.0
Command Reply Description
C 1Hn &| Sets n as the maximum value of the measuring range of
the physical quantity associated to the analog output 1.
If the output is associated to PM, the value must be ex-
pressed as a number of tenths (e.g. n=50 to indicate 5.0
µg/m
3
). If the output is associated to CO
2
, the value must
be expressed as a number of units (e.g. n=800 to indicate
800 ppm).
Default : 10000 (=1000.0 µg/m
3
of PM)
R 1H & n| Reads the maximum value of the measuring range of the
physical quantity associated to the analog output 1.
R 1F & Quantity
Minimum value
Maximum value
Simultaneously provides the information obtainable with
the R 1T, R 1L e R 1H commands.
C 2On &| Enable/disable the offset of the analog output 2:
Offset disabled if n=0 (0…20 m or 0…10 V)
Offset enabled if n=1 (4…20 m or 2…10 V)
Default : Offset enabled (n=1) if the output is current,
offset disabled (n=0) if the output is voltage (optional)
R 2O & n| Reads the setting of the offset for the analog output 2.
C 2SOn &| Sets the direct or inverse correspondence between analog
output 2 and associated physical quantity:
4 m /0 V  Min. quantity, 20 m /10 V  Max.
quantity if n=0
20 m /10 V  Min. quantity, 4 m /0 V  Max.
quantity if n=1
Default : Direct correspondence (n=0)
R 2SO & n| Reads the type of correspondace (direct or inverse) be-
tween analog output 2 and associated physical quantity.
C 2Tn &| ssociates the analog output 2 to:
PM1.0 if n=0
PM2.5 if n=1
PM10 if n=2
CO
2
if n=12 (only PMBsense- )
Default : PM10 (n=2)
Note: the PM measurement is updated according to the op-
erating mode set with the CP S, CP P and CPS commands.
R 2T & n| Reads the physical quantity associated to analog output 2.
C 2Ln &| Sets n as the minimum value of the measuring range of
the physical quantity associated to the analog output 2.
If the output is associated to PM, the value must be ex-
pressed as a number of tenths (e.g. n=5 to indicate 0.5
µg/m
3
). If the output is associated to CO
2
, the value must
be expressed as a number of units (e.g. n=200 to indicate
200 ppm).
Default : 0
R 2L & n| Reads the minimum value of the measuring range of the
physical quantity associated to the analog output 2.

PMsense - 13 - V1.0
Command Reply Description
C 2Hn &| Sets n as the maximum value of the measuring range of
the physical quantity associated to the analog output 2.
If the output is associated to PM, the value must be ex-
pressed as a number of tenths (e.g. n=50 to indicate 5.0
µg/m
3
). If the output is associated to CO
2
, the value must
be expressed as a number of units (e.g. n=800 to indicate
800 ppm).
Default : 10000 (=1000 µg/m
3
of PM)
R 2H & n| Reads the maximum value of the measuring range of the
physical quantity associated to the analog output 2.
R 2F & Quantity
Minimum value
Maximum value
Simultaneously provides the information obtainable with
the R 2T, R 2L e R 2H commands.
Reading of the measurement information:
Command Reply Description
S0 &| Disable the sending of the measurement information.
S1 &| Enable the sending of the measurement information
every second.
For the meaning of the information sent by the instru-
ment, see the command S5.
S5 & Measurements Prints the list of the measurement information sent by
the instrument, in the following sequence:
PM measurement error (0=no, 1=yes)
PM1.0 in µg/m
3
PM2.5 in µg/m
3
PM10 in µg/m
3
CO
2
in ppm
tmospheric pressure in hPa (internal sensor for
CO
2
measurement compensation)
Field not used
Field not used
Field not used
Power supply voltage
Internal board temperature
Note: the PM measurement is updated according the oper-
ating mode set with the CP S, CP P and CPS commands.

PMsense - 14 - V1.0
CO
2
calibration (only PMBsense…):
2-point (CO21 and CO22 commands) or 1-point calibration (CO2O command) can
be performed. The points are chosen by the user. To perform the calibration, the
transmitter must be placed in an environment with a known CO
2
concentration.
While the 2-point calibration allows moving the two calibration points independently,
and therefore also to adjust the slope of the sensor response curve, the 1-point cali-
bration simply adds an offset to the measurement (the two calibration points are
shifted of the same amount) and is typically accomplished by placing the transmitter
in clean air.
Before performing the calibration, the type of calibration to be used must be set to
“user” with the CC command.
The transmitter allows manually setting, with the D command, a string that is saved
as the date and time of the calibration. The string must be set before performing the
calibration.
Command Reply Description
CO21n & t| CO
2
calibration in the first point at n ppm.
The transmitter must first be placed in an environment
with a known CO
2
concentration (the value n entered in
the command).
The value t in the reply to the command indicates the
number of seconds required for the transmitter to com-
plete the calibration operation. During this time, the
transmitter sends strings notifying the progress of the
operation; for example:
“CO2 calib. Status:IN PROGRESS 8% vg:1096ppm Dev:0ppm”
t the end, the OK 100% notification indicates that the
operation was successful; for example:
“CO2 calib. Status:OK 100% vg:1100ppm Dev:7ppm”
CO22n & t| CO
2
calibration in the second point at n ppm.
Operation similar to the CO21command.
CO2On & t| CO
2
calibration at n ppm (1-point calibration – offset ad-
justment).
Operation similar to the CO21command.
D yyyy/mm/dd
hh:mm:ss
&| Saves the string “aaaa/mm/gg hh:mm:ss” as the date
and time when calibration is performed.
The command must be sent before performing the cali-
bration.
G & yyyy/mm/dd
hh:mm:ss
Reads the date and time saved with the D command.
CCn &| Sets the type of calibration to be used:
User if n=0
Factory if n=1
Default : Factory (n=1)
CO2D &| Reset of user calibration.
Restoring the factory configuration:
Command Reply Description
DFLT &| Restores the factory configuration.

PMsense - 15 - V1.0
6MODBUS-RTU PROTOCOL
By default, the instrument has MODBUS address 1 and communication parameters
19200, 8E1. The address and the communication parameters can be changed by using
the appropriate serial commands of the proprietary protocol or, alternatively, directly
with MODBUS commands by changing the value of the Coils and Holding Registers de-
scribed later.
The MODBUS-RTU protocol, if set as the operating protocol (default), is active after 10
seconds from the instrument power on.
In order to change the instrument configuration using the MODBUS-RTU protocol, the
value 1 must be written first in the Coil number 2 (address 1).
Below is the list of registers (the tables show both the number and the address of the
registers, with the address of the register equal to the number of the register de-
creased by 1, as defined in the MODBUS standard).
Input Registers:
Number Address Description Format
1 0 PM1.0 in N° of particles/ml.
Measurement updated according the operating mode set
with the CP S, CP P and CPS commands.
16-bit Integer
2 1 PM2.5 in N° of particles/ml.
Measurement updated according the operating mode set
with the CP S, CP P and CPS commands.
16-bit Integer
3 2 PM10 in N° of particles/ml.
Measurement updated according the operating mode set
with the CP S, CP P and CPS commands.
16-bit Integer
4 3 PM1.0 in µg/m
3
(x10).
Measurement updated according the operating mode set
with the CP S, CP P and CPS commands.
16-bit Integer
5 4 PM2.5 in µg/m
3
(x10).
Measurement updated according the operating mode set
with the CP S, CP P and CPS commands.
16-bit Integer
6 5 PM10 in µg/m
3
(x10).
Measurement updated according the operating mode set
with the CP S, CP P and CPS commands.
16-bit Integer
7 6 PM1.0 in N° of particles/ml.
Measurement averaged over 10 s and updated every
second. Available in continuous measurement mode.
16-bit Integer
8 7 PM2.5 in N° of particles/ml.
Measurement averaged over 10 s and updated every
second. Available in continuous measurement mode.
16-bit Integer
9 8 PM10 in N° of particles/ml.
Measurement averaged over 10 s and updated every
second. Available in continuous measurement mode.
16-bit Integer
10 9 PM1.0 in µg/m
3
(x10).
Measurement averaged over 10 s and updated every
second. Available in continuous measurement mode.
16-bit Integer

PMsense - 16 - V1.0
11 10 PM2.5 in µg/m
3
(x10).
Measurement averaged over 10 s and updated every
second. Available in continuous measurement mode.
16-bit Integer
12 11 PM10 in µg/m
3
(x10).
Measurement averaged over 10 s and updated every
second. Available in continuous measurement mode.
16-bit Integer
13 12 PM1.0 in N° of particles/ml.
Measurement averaged over 60 s and updated every
10 s. Available in continuous measurement mode.
16-bit Integer
14 13 PM2.5 in N° of particles/ml.
Measurement averaged over 60 s and updated every
10 s. Available in continuous measurement mode.
16-bit Integer
15 14 PM10 in N° of particles/ml.
Measurement averaged over 60 s and updated every
10 s. Available in continuous measurement mode.
16-bit Integer
16 15 PM1.0 in µg/m
3
(x10).
Measurement averaged over 60 s and updated every
10 s. Available in continuous measurement mode.
16-bit Integer
17 16 PM2.5 in µg/m
3
(x10).
Measurement averaged over 60 s and updated every
10 s. Available in continuous measurement mode.
16-bit Integer
18 17 PM10 in µg/m
3
(x10).
Measurement averaged over 60 s and updated every
10 s. Available in continuous measurement mode.
16-bit Integer
19 18 PM1.0 in N° of particles/ml.
Measurement averaged over 15 min and updated every
minute. Available in continuous measurement mode.
16-bit Integer
20 19 PM2.5 in N° of particles/ml.
Measurement averaged over 15 min and updated every
minute. Available in continuous measurement mode.
16-bit Integer
21 20 PM10 in N° of particles/ml.
Measurement averaged over 15 min and updated every
minute. Available in continuous measurement mode.
16-bit Integer
22 21 PM1.0 in µg/m
3
(x10).
Measurement averaged over 15 min and updated every
minute. Available in continuous measurement mode.
16-bit Integer
23 22 PM2.5 in µg/m
3
(x10).
Measurement averaged over 15 min and updated every
minute. Available in continuous measurement mode.
16-bit Integer
24 23 PM10 in µg/m
3
(x10).
Measurement averaged over 15 min and updated every
minute. Available in continuous measurement mode.
16-bit Integer
27 26 PM measurement error: 0=no, 1=yes. Intero 16 bit
29 28 CO
2
in ppm. Intero 16 bit
34,35 33,34 tmospheric pressure in Pa
(*)
Internal sensor for CO
2
measurement compensation
Intero 16 bit
36 35 tmospheric pressure in hPa (x10)
Internal sensor for CO
2
measurement compensation
Intero 16 bit
38 37 Power supply voltage in Volt (x10). 16-bit Integer

PMsense - 17 - V1.0
39 38 Internal board temperature (x10). 16-bit Integer
41 40 Instrument firmware
revision. The most significant byte
indicates the major revision; the less significant byte
indicates the minor revision.
16-bit Integer
42 41 Number of MODBUS communication error. 16-bit Integer
(*)
The measure is a 32-bit integer value. Two consecutive registers must be accessed to read
the value. The register with lower address contains the most significant bits.
Coils:
Number Address Description Format
1 0 Set 1 to restore the factory configuration. Bit zeroing
is automatic.
Bit
2 1 Enable configuration change:
0=no (default), 1=yes.
The changes to Coils and Holding Registers will be ac-
cepted only if this register is set to 1.
Bit
3 2 Sets waiting time after transmission with MODBUS-RTU
protocol:
0=immediate reception (default);
1=waiting 3.5 characters.
Bit
4 3 Enable/disable the offset of the analog output 1:
0=offset disabled (0…20 m or 0…10 V, default if the
output is voltage);
1=offset enabled (4…20 m or 2…10 V, default if the
output is current).
Bit
5 4 Sets the direct or inverse correspondence between ana-
log output 1 and associated physical quantity:
0=4 m /0 V  Min. quantity, 20 m /10 V  Max.
quantity (default);
1=20 m /10 V  Min. quantity, 4 m /0 V  Max.
quantity.
Bit
6 5 Enable/disable the offset of the analog output 2:
0=offset disabled (0…20 m or 0…10 V, default if the
output is voltage);
1=offset enabled (4…20 m or 2…10 V, default if the
output is current).
Bit
7 6 Sets the direct or inverse correspondence between ana-
log output 2 and associated physical quantity:
0=4 m /0 V  Min. quantity, 20 m /10 V  Max.
quantity (default);
1=20 m /10 V  Min. quantity, 4 m /0 V  Max.
quantity.
Bit

PMsense - 18 - V1.0
Holding Registers:
Number Address Description Format
1 0 RS485 Baud Rate:
0=1200;
1=2400;
2=4800;
3=9600;
4=19200 (default);
5=38400;
6=57600;
7=115200.
16-bit Integer
2 1 RS485 parity and stop bits:
0=8N1;
1=8N2;
2=8E1 (default);
3=8E2;
4=8O1;
5=8O2.
[N=no parity, E=even parity, O=odd parity]
16-bit Integer
3 2 Instrument address for the MODBUS-RTU protocol
(1…247, default=1).
16-bit Integer
4 3 ssociation of a physical quantity to the analog output 1:
0=PM1.0;
1=PM2.5 (default);
2=PM10;
12=CO
2
(only PMBsense- ).
Note: the PM measurement is updated according to the
set operating mode.
16-bit Integer
7,8 6,7 Setting of the minimum value of the measuring range of
the physical quantity associated to the analog output 1.
(*)
If the output is associated to PM, the value is expressed
as a number of tenths (e.g. 5 = 0.5 µg/m
3
). If the output
is associated to CO
2
, the value is expressed as a number
of units (e.g. 200 = 200 ppm). The default value is 0.
16-bit Integer
9,10 8,9 Setting of the maximum value of the measuring range of
the physical quantity associated to the analog output 1.
(*)
If the output is associated to PM, the value is expressed
as a number of tenths (e.g. 50 = 5.0 µg/m
3
). If the out-
put is associated to CO
2
, the value is expressed as a
number of units (e.g. 800 = 800 ppm). The default value
is 10000 (=1000.0 µg/m
3
of PM).
16-bit Integer
11 10 ssociation of a physical quantity to the analog output 2:
0=PM1.0;
1=PM2.5;
2=PM10 (default);
12=CO
2
(only PMBsense- ).
Note: the PM measurement is updated according to the
set operating mode.
16-bit Integer

PMsense - 19 - V1.0
Number Address Description Format
12,13 11,12 Setting of the minimum value of the measuring range of
the physical quantity associated to the analog output 2.
(*)
If the output is associated to PM, the value is expressed
as a number of tenths (e.g. 5 = 0.5 µg/m
3
). If the output
is associated to CO
2
, the value is expressed as a number
of units (e.g. 200 = 200 ppm). The default value is 0.
16-bit Integer
14,15 13,14 Setting of the maximum value of the measuring range of
the physical quantity associated to the analog output 2.
(*)
If the output is associated to PM, the value is expressed
as a number of tenths (e.g. 50 = 5.0 µg/m
3
). If the out-
put is associated to CO
2
, the value is expressed as a
number of units (e.g. 800 = 800 ppm). The default value
is 10000 (=1000.0 µg/m
3
of PM).
16-bit Integer
16 15 Setting of the PM measurement mode:
0=continuous;
1=at cyclic intervals (default).
16-bit Integer
17 16 Setting of the cycle interval, in seconds, for the PM
measurement mode at cyclic intervals.
The number of seconds must be greater than 70, in
order to allow the sensor to take the measurement.
The default value is 300 (=5 min).
16-bit Integer
Unsigned
20 19 Setting of the type of measurement averaging for the
continuous PM measurement mode:
0=average over a 10 seconds interval, updated every
second;
1=average over a 60 seconds interval, updated every
10 seconds (default);
2=average over a 15 minutes interval, updated every
minute.
16-bit Integer
21 20 Setting of the type of CO
2
calibration to be used:
0=user;
1=factory (default).
16-bit Integer
(*)
The datum is a 32-bit integer value. Two consecutive registers must be accessed to
read/write the value. The register with lower address contains the most significant bits.

PMsense - 20 - V1.0
7SAFETY INSTRUCTIONS
General safety instructions
The instrument has been manufactured and tested in accordance with the safety
standard EN61010-1:2010 “Safety requirements for electrical equipment for meas-
urement, control and laboratory use” and has left the factory in perfect safety tech-
nical conditions.
The instrument proper operation and operating safety can be ensured only if all
standard safety measures as well as the specific measures described in this manual
are followed.
The instrument proper operation and operating safety can be ensured only in the cli-
matic conditions specified in this manual.
Do not use the instruments in places where there are:
•Corrosive or flammable gases.
•Direct vibrations or shocks to the instrument.
•High-intensity electromagnetic fields, static electricity.
User obligations
The instrument operator shall follow the directives and regulations below that refer to
the treatment of dangerous materials:
•EEC directives on workplace safety.
•National law regulations on workplace safety.
•ccident prevention regulations.