Sensitron PL4 +D Reference manual

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PL4 +D
ATEX and SIL 1 certified
MANUAL FOR INSTALLATION
AND USE
SENSITRON S.r.l. Viale della Repubblica, 48
20010 CORNAREDO MI - Italy
Tel: + 39 02 93548155 Fax: + 39 02 93548089
E-MAIL: [email protected]

Technical manual PL4 +D
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Avvertenze
THIS MANUAL MUST BE CAREFULLY READ BY ALL PERSONS WHO
ARE OR WILL BE RESPONSIBLE FOR INSTALLING, USING OR
SERVICING THIS PRODUCT.
Like any equipment, this product will perform as designed only if installed,
used and serviced in accordance with the manufacturer’s instructions.
This product must be installed by qualified technician.
OTHERWISE, IT COULD FAIL TO PERFORM AS DESIGNED AND
PERSONS WHO RELY ON THIS PRODUCT FOR THEIR SAFETY
COULD SUFFER SEVERE PERSONAL INJURY OR DEATH.
Sensitron S.r.l provides a guarantee for the product supplied. This
guarantee lapses if installation, use or maintenance are not carried out in
accordance with the instructions of this manual.
For further information about installation, maintenance and, eventually,
restoration of this product, please contact Sensitron S.r.l.

Technical manual PL4 +D
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THIS TECHNICAL MANUAL DESCRIBES THE PRODUCT
IN ITS COMPONENTS, THE INSTALLATION AND THE
OPERATION OF THE SYSTEM. THE CONFIGURATION
SOFTWARE IS NOT INCLUDED, SO PLEASE REFER TO
THE PROPER MANUAL.

Technical manual PL4 +D
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INDEX
1) INTRODUCTION................................................................................................................................... 5
1.1) BLOCK DIAGRAM SYSTEM WITH PL4 +D GAS CONTROL UNIT................................................................ 7
1.2) TECHNICAL SPECIFICATIONS.............................................................................................................. 7
2) INSTALLATION.................................................................................................................................... 8
2.1) ASSEMBLY AND CONNECTIONS.......................................................................................................... 8
2.1.1) UNIT DIAGRAM AND PART IDENTIFICATION ................................................................................... 9
2.1.2) LAYOUT PL4 +D GAS CONTROL UNIT........................................................................................ 10
2.2) FIELD DEVICE CONNECTIONS........................................................................................................... 12
2.2.1) DETECTOR CONNECTION ......................................................................................................... 13
2.3) STG/IN8-S REMOTE INPUT MODULES.............................................................................................. 18
2.4) STG/OUT16-S REMOTE OUTPUT MODULES..................................................................................... 19
2.4.1) STG/8REL RELAY EXPANSION BOARD ..................................................................................... 20
2.4.2) ST.G/IN8-S AND ST.G/OUT16-S MODULE ADDRESSING.......................................................... 20
2.5) PROGRAMMING FROM A PC ............................................................................................................ 22
3) SYSTEM POWER UP AND OPERATION.......................................................................................... 22
3.1) POWER ON.................................................................................................................................... 22
3.2) SYSTEM STATUS............................................................................................................................. 23
USER LEVEL.......................................................................................................................................... 25
THE USER PASSWORDS CAN BE CREATED AND/MODIFIED JUST BY THE PC CONFIGURATION SOFTWARE.......... 26
3.3) MENU ............................................................................................................................................ 27
In normal status, the main screen shows the terminal name, the time and the indication to press the
operative keys of vertical movement to visualize the connected detectors. .............................................. 27
3.4) ACTIVE EVENTS AND EVENT MANAGEMENT....................................................................................... 28

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1) INTRODUCTION
The highly innovative and versatile PL4 +D gas unit is the ideal solution for small systems with
up to 16 gas detectors.
The system provides for the direct connection of 4 detectors to the gas unit (4-20mA) and to
additional 8 detectors that can be connected directly to the RS485 bus or via a remote module
with 8 x STG/IN8-S inputs (optional).
Each input can be configured for different types of gas: toxic, refrigerant, flammable, and
oxygen, both for their deficiency and enrichment.
The backlit display offers an accurate indication of gas concentration and allows the display of
established alarm levels.
The gas control unit manages up to 21 relay outputs, of which 5 are on board the gas control
unit and the other 16 are via STG/OUT16S and STG/8REL cards (optional).
The housing of gas control unit is a plastic box 9 DIN module. A further plastic box, 12 DIN
module can be supplied as optional.
The gas control unit power is 24Vdc (power sully available on request).
The PL4 +D is SIL1 and ATEX certified pursuant to EN60079-29-1.
158,50 mm
90,00mm 45,00mm
60,00 mm
Fig. 1.) Gas control unit PL4 +D and its dimensions
Overview of devices connectable to the PL4 +D gas control unit.
Gas control model
N. serial bus
RS485
N. max
detectors
N. max
outputs
ST.G/IN8
N. max
modules
ST.G/OUT16
N. max
modules
Notes
PL4 +D
1
4+8(*)
5+16(*)
1
1
(*) available through additional modules
Other features of the PL4 +D, gas control unit are:
•Event log can be displayed on the screen or downloaded to a PC.
•USB port for PC connection for programming and control via specific software.

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Gas control unit ordering codes and accessories
CODE
DESCRIPTION
STPL4+D
PL4 +D gas control panel.
4 Analog 4-20mA inputs and 6 relay outputs on-board the panel.
1 x RS485 type open bus line to connect additional 8 detectors through
remote 8-input module or addressable gas detectors daisy chained to the
RS485 bus.
5 relay outputs and additional 16 o/c via the dedicated STG/OUT16-S and
STG/8REL cards.
ACCESSORIES
CODE
DESCRIPTION
STG/IN8-S
High safety 8-input remote module for PL4 +D control panel.
STG/OUT16-S
16 O/C card to be connected to PL4 +D to provide additional 16 outputs
STG/8REL
Plug and play relay board to be connected to STG/OUT16 to provide 8 relay outputs
xxxx
Power supply 24Vdc 2A for DIN plank.
xxxx
IP65 plastic box, 12 module.
STG/MTSS1-
CONF
Windows PC software for PL4 +D control panel programming. Running under
Windows XP, VISTA, WIN7, 8, 8.1, 10.
The configuration software is supplied along with the control panel

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1.1) Block diagram system with PL4 +D gas control unit
LOOP
(6)
Rs485
option: the detectors could be connected
directly on the loop in daisy-chain mode
(1) RILEVATORI GAS ANALOGICI 4-20 mA / 4-20 mA ANALOG GAS DETECTORS
(2) MODULO 8 INGRESSI ANALOGICI ST.G/IN8-S / ANALOG 8 INPUT MODULE
ST.G/IN8-S
(3) CAVO 2 FILI TWISTATI PER Rs485 + 2 FILI PER ALIMENTAZIONE (12-24 Vdc) /
2 TWISTED WIRES FOR THE Rs485 BUS + 2 WIRES FOR THE POWER SUPPLY (12-24 Vdc)
(4) RILEVATORI GAS CON USCITA SERIALE Rs485 / GAS DETECTORS WITH Rs485 OUTPUTS
(5) MODULO 16 USCITE O/C ST.G/OUT16-S / 16 O/C OUTPUTS MODULE ST.G/OUT16-S
(6) MODULO 8 RELE’ ST.G/8REL / 8 RELE’ ST.G/8REL MODULE
(1)
(2)
(3)
(4)
(5)
Pl4 +D
(1)
Fig. 1.1) System block outline
1.2) Technical specifications
Technical specifications
Housing:
IP65 plastic box, 9 DIN module
Inputs:
Max. 12 detectors
Outputs:
5 relays in the gas control unit
16 O/C or relay outputs via the STG/OUT16-S and STG/8REL
remote cards.
Serial ports:
1 x RS485
1 x USB (PC connection)
Power:
24Vdc
Absorption:
Max 10 VA
Display:
Liquid crystal display (LCD)
Optic indications:
10 LEDS
Working temp.
0/-55°C
Storage temp.
-20 ÷ +60 C°
Working RH:
15-85%
Storage RH:
5-85% (non-condensing)

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2) INSTALLATION
2.1) Assembly and connections
Insert the gas control unit on DIN plank.
Fig. 2.1 a) Gas control unit and its box (optional)
Connect the cable for power supply (24 Vdc) to the terminal block of gas control unit.
- +
Fig. 2.1 b) Power connection

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2.1.1) Unit diagram and part identification
5
4
321
1- Power Supply (24 Vdc)
2- Relay outputs (5)
3- USB port
4- RS485 bus connection
5- 4 inputs 4-20 mA
Fig. 2.1.1) Unit diagram and part identification

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2.1.2) Layout PL4 +D gas control unit
Sd3: dip switch per settaggio lingua Sd3: dip switch for language setting
3 switc hes: Control panel la nguage
Language Sw1
Sw4 Sw3 Sw2
English
Italian
Spanish
Portuguese
German
French
Slovenian ON
OFF
ON ON ON ON ON ON ON
ON ON ON
ON ON ON ON ON
OFF OFF
OFF
OFF
OFF OFF
OFF OFF OFF OFF OFF
4 X INGRESSIANALOGICI 4-20mA
4 x 4-20 mAANALOG INPUTS
5 X USCITE RELE’/ 5 X RELAY OUTPUTS
LINEASERIALE Rs485 Rs485 SERIAL LINE
USBFORPC CONNECTION
POSITIVO E NEGATIVO DALL’ALIMENTATORE 24Vdc POSITIVEAND NEGATIVE FROM POWERSUPPLY 24 Vdc
ABH
5 4 3 2 1 +
-
NO: Normally Open C: Common NC: Normally Closed
NO: Normalmente aperto C: Comune NC: Normalmente chiuso
SD
Sd4: dip switch per filtro su segnale analogico Sd4: dip switch for filter on analogue signal Sd4 switches:
filter on analogue signal Filter Sw1 Sw2 NO OFF OFF 5s ON OFF 10s OFF ON 15s ON ON
Jp25: JP1-2 chiuso Jp25: JP1-2 closed
Sd2: dip switch per Baud Rate Sd2: dip switch forBaud Rate
Fig. 2.1.2) Layout PL4 +D gas control unit

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2.1.3) Dip switch SD2, SD3 and SD4 settings
The series of SD2 dip-switches is used to set the terminal unit to the RS485 bus of gas
control unit.
The series of SD3 dip switches allows to set the language of text on the display of the
remote terminal.
The series of SD4 dip switches is used to set a filter on analogue input. If a noise
caused a false alarm, the filter avoids the trigger of an alarm for a time duration chosen
by the operator. The user can set the time interval though the attached table.
Sd3: dip switch per settaggio lingua
Sd3: dip switch for language setting
3 switches: Control panel language
Language Sw1Sw4 Sw3 Sw2
English
Italian
Spanish
Portuguese
German
French
Slovenian ON
OFFON
ON
ON
ON
ON
ON
ON
ON
ON
ON
ON ON
ON
ON ON
OFF OFF
OFF
OFF
OFF OFF
OFF OFFOFF
OFF OFF
SD
Sd4: dip switch per filtro su segnale analogico
Sd4: dip switch for filter on analogue signal Sd4 switches:
filter on analogue signal
Filter Sw1 Sw2
NO OFF OFF
5s ON OFF
10s OFF ON
15s ON ON
Fig. 2.1.4 a) Dip-switch SD3 and SD4
IngressoUSB
Sd2: dip switch per Baud Rate
Sd2: dip switch forBaud Rate
Fig. 2.1.4 b) Dip-switch SD2

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Dip-switch 1: Baud Rate Bus RS485
Position
Bus communication speed
Detector and module compatibility
ON
115200
Smart “S” gas detectors; ST.G/IN8-S and
ST.G/OUT16-S modules
OFF
9600
Smart “3G” gas detectors; ST.G/IN8-S and
ST.G/OUT16-S modules
Dip-switches 2 and 3: RS485 bus communication protocol
Sw 2
Sw 3
Protocol
Detector and module
compatibility
Notes
ON
ON
Galileo
Smart “S” gas detectors;
ST.G/IN8-S and ST.G/OUT16-
S modules
Baud Rate 115200
OFF
ON
NU
NU
NU
ON
OFF
Modbus
Smart "G" gas detectors;
STG/IN8-S and STG/OUT16-S
modules
Baud rate 9600 (if they are
not connected to the Smart
"G" bus detectors, 115200
Bps can be set (switch 1)
OFF
OFF
Setting not used
Dip-switches 4 and 5: Communication (baud rate) with the PC
Sw 4
Sw 5
Baud Rate
ON
ON
9600 Bit/sec.
OFF
ON
19200 Bit/sec.
ON
OFF
38400 Bit/sec.
OFF
OFF
115200 Bit/sec. (default)
Dip-switches 6 and 7: not used
Dip-switch 8: restore default settings
Position
Function
ON
If set to ON, default data is restored when the gas control unit is switched on
OFF
Normal position
2.2) Field device connections
The gas control unit has 1 RS485 data bus to which 8 gas detectors can be connected
The gas detectors are connected through the serial bus (directly in the serial RS485 if equipped
with serial output or through 1 module with 8 STG/IN8 S inputs if of type 4-20 mA) and the
ST.G/OUT16-S output module
The maximum length of each serial data bus is 800 m.
To connect devices, 4 conductors are required (intended both as detectors with a serial output
as well as IN and OUT modules): 2 for the RS485 serial bus and two for powering the devices.
For this reason, two different wires must be used or a single wire that has suitable
characteristics, as described below.

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-) The RS485 serial bus must be connected with an EIA RS 485 connection wire: No. 2 wires
with 0.22/0.35 mm2 section with shield (TWISTED PAIR). Nominal capacity between
conductors < 50 pF/m, nominal impedance 120 ohm. Total line length with this type of
connection must not exceed 1,000 metres. An example of a recommended cable is a BELDEN
9841 or similar wire (EIA RS485 data transmission wire). Only connect detectors (and IN and
OUT modules) in a "cascading" manner. Avoid tree or star connections since they reduce
interference immunity.
-) Detector power supply (and IN and OUT modules on the bus) must be connected with a 2-
core wire with adequate section based on the number of connected devices, their distance from
the power supply and each device’s consumption (please see the technical manual enclosed
with gas detectors for this purpose).
Each device connected on the unit's RS485 bus must have its own univocal address. See the
appropriate section of this manual to set the address of the STG/IN8 S and STG/OUT16-S
modules, and see the relative manual for setting the detector address.
2.2.1) Detector connection
Gas detectors can be connected to the PL4 +D gas control unit in two different ways,
based on the detector output signal.
1) 4-20 mA analogue proportional output.
The detector connected to the unit and ST.G/IN8 S module will send a 4-20 mA signal
referring to its range (i.e. 0-300 ppm, 0-30 ppm, 0-100% LEL etc.) and the unit, suitably
programmed, will display the relevant gas concentration indication measured by the
detector and consequently activate the alarms when the set values are reached.
2) RS485 digital proportional output
The detector connected to the gas control unit will send a data signal on the RS485 line.
This signal refers to the range of the detector (i.e. 0-300 ppm, 0-30 ppm, etc.); the unit,
suitably programmed, will display the relevant gas concentration indication measured by
the detector and consequently activate the alarms when the set values are reached

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Detectors with 4-20mA output
Detectors with 4-20mA analogue output are either connected to the gas control unit, directly on
the main board or via one remote 8-input STG/IN8-S module. The module may be connected
remotely to the gas control unit. For connection, a detector with a 4-20mA analogue output
requires a 3-conductor cable: 2 conductors for the power supply (usually from 12 to 28 Vdc -
refer to the gas detector technical manual) and one conductor for the 4-20mA signal. The
generally recommended cable is a shielded 3 x 0.75, which allows up to 100 meters between
the gas detector and STG/IN8-S input module
Detectors with 4-20 mA output directly connected to the gas control unit
+V 1 2 3 4 -V
Fig. 2.2.1 a) Connection of the 8 detectors of the gas control unit
Detectors with a 4-20 mA output connected to the ST.G/IN8-S module
The following diagram shows the connection of a gas detector with a 4-20 mA output to a
STG/IN8-S input module. During system start-up, make sure that each gas detector reaches a
minimum voltage of 12 Vdc.
-V
I8
I7
I6
I5
+V
-V
I4
I3
I2
I1
+V
-V
B
A
+V
REMOTE INPUT
MODULE ST/G.IN8
(+V) (-V)
(S)
Positive
Negative
4-20 mA signal
4-20 mA
analog
gas
detector
Rilevatore
analogico
4-20 mA
MODULO INGR.
4-20 mA ST/G.IN8
Fig. 2.2.1 b) connnection of the 8 detectors of the ST.G/IN8-S module

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Detectors with RS485 output
Gas detectors provided with RS485 serial communication are connected directly to the RS485
bus of the PL4 +D gas control unit. The STG/IN8-S input module and STG/OUT16-S output
module are also connected to the RS485 bus.
4 conductors are needed for this type of connection: 2 for the RS485 serial and 2 for the power
supply of devices. For this reason, we suggest that two different wires or a single wire is used.
with the features described below.
-) The RS485 serial bus must be connected with an EIA RS 485 connection wire: No. 2 wires
with 0.22/0.35 mm2 section with shield (TWISTED PAIR). Nominal capacity between
conductors < 50 pF/m, nominal impedance 120 ohm. Total line length with this type of
connection must not exceed 1,000 metres. An example of a recommended cable is a BELDEN
9841 or similar wire (EIA RS485 data transmission wire). Only connect detectors (and IN and
OUT modules) in a "cascading" manner. Avoid tree or star connections since they reduce
interference immunity.
-) The power supply to the detectors (and IN and OUT modules on the bus) must be connected
with a 2-core wire with adequate section based on the number of connected devices, their
distance from the power supply and each device’s consumption (please see the technical
manual enclosed with gas detectors for this purpose).
Note: each detector connected on the RS485 line must have its own univocal address between
1 and 255 (247 for the ModBus protocol). Please see the gas detector technical manual for
address settings.
The diagram below shows the connection of IN and OUT detectors and remote modules on the
RS485 bus of the gas control unit

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d
+
A B
Dalla centrale o dall’alimentatore ausiliario remoto From the control panelor from the remote auxiliary power supply
Cavo twistato / schermato 2x022 (Belden9841 oequivalente)
Twisted / shielded 2x0,2 cable (Belden 9841 or equivalent)
H
-
Pl4 +D
+ - A B
+ - A B
+ - A B
+ - A B
OUTPUT MODULE
+ - A B
Al rilevatore o modulo successivo
To the next detector or module
Fig 2.2.1 c) Direct connection of detectors on the RS485 bus

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d
+
A B
Dalla centrale o dall’alimentatore ausiliario remoto From the control panel or from the remote auxiliary power supply
Cavo twistato / schermato 2x022 (Belden 9841 o equivalente)
Twisted / shielded 2x0,2 cable (Belden 9841 or equivalent)
-V I8 I7 I6 I5 +V -V I4 I3 I2 I1 +V
-V B A +V
REMOTE INPUT MODULEST/G.IN8
MODULO INGR. 4-20 mA ST/G.IN8
H
-
+ s - 4-20mA
GAS DETECTOR
(up to 8)
STG/IN8
MODULE
Pl4 +D
Fig 2.2.1 d) Detector connection by STG/IN8-S

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2.3) STG/IN8-S remote input modules
STG/IN8-S remote modules are field mounted and connected to the gas control unit via
RS485 buses. They are used to connect 8 x 4-20mA analogue gas detectors. Each
module must be addressed using the rotary switches on the PCB. The address must be
univocal and between 1 and 255 (1-247 for Modbus protocol). See the summary table in
para. X for the maximum number of connectable modules to the gas control unit. 1)
INTRODUCTION
Jumper da non manomettere
/ jumpers not to be touched
Jp1
Jp2
Jp3
Jp4
Jp9
Jp11
Jp12
Jp14
Closed 1-2
Closed
Closed
Open Open
Open
Closed 1-2
Led
DL1: Guasto WD /WD Faul
DL2: TX Data
DL3: RX Data
DL4: RTS
Jp10 Resistenza di file linea
(EOL resistor)
Se il modulo è l’ultimo della linea chiudere Jp10
/ If the module is the last of the bus line, close JP10
A
B
Rs485 serial line
Morsettiera alimentazione e linea seriale
(Power supply and serial line)
Jp13 Communication Baud Rate setting:
Closed 115.000 bps (Multiscan++ control panel
Open 9.600 bps (old Galileo Multiscan control panel)
Jp13 Settaggio velocità comunicazione:
Chiuso 115.000 bps (Centrale Multiscan ++)
Aperto 9.600 bps (vecchia centrale Galileo Multiscan)
Commutatori rotativi
per l’indirizzo del modulo
Channels 5-8 Channels 1-4
-V +V-V +V
Morsettiera rilevatori
(gas detector connections)
Open
Rotary switches for
the module address)
Fig. 2.3) ST.G/IN8-S module

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2.4) STG/OUT16-S remote output modules
STG/OUT16-S remote modules are field mounted and connected to the gas control unit via
RS485 buses. They provide 16 Open Collector outputs (negative switch) with a programmable
function for the remote activation of sirens, solenoid valves, relays, etc. Up to 2 8-relay boards
can be connected to each STG/OUT16-S module, transforming the output from Open Collector
to a voltage-free exchange contact.
See the summary table in para. X for the maximum number of connectable modules to the gas
control unit. 1) INTRODUCTION
Each module must be addressed using the rotary switches on the PCB. The address must be
univocal and between 1 and 255 (1-247 for the Modbus protocol).
Morsettiera alimentazione
e linea seriale
(Power supply and serial line)
Commutatori rotativi per
l’indirizzo del modulo
Jp13 Communication Baud Rate setting:
Closed 115.000 bps
(Multiscan++ control panel
Open 9.600 bps
(old Galileo Multiscan control panel)
Jp13 Settaggio velocità comunicazione:
Chiuso 115.000 bps
(Centrale Multiscan ++)
Aperto 9.600 bps
(vecchia centrale Galileo Multiscan)
Led
DL1: Guasto WD /WD Faul
DL2: TX Data
DL3: RX Data
DL4: RTS
Resistenza di file linea
(EOL resistor)
chiudere s
close i
è l’ultimo della linea /
f the module
is the last of the bus line
e il modulo
-V +V -V
Morsettiera uscite O/Ci
(O/C output connections)
Outputs 9-16 Out 1-8
A
B
Rs485 serial line
Collegamento scheda relè (opzionale)
/ Relay board connection (optional)
Jumper da non manomettere
/ jumpers not to be touched
Jp5
Jp6
Jp7
Jp8
Jp9
Jp11
Jp12
Closed 1-2
Closed
Closed
Open
Open
Open
Open
Rotary switches
for the module address
+V
+V
+V
Esempio di collegamento relè
Example of relay connection
Fig. 2.4) STG/OUT16-S module

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2.4.1) STG/8REL relay expansion board
The STG/8REL 8-relay expansion board converts the O/C outputs of the STG/OUT16-S output
module into voltage-free exchange contacts. Up to two relay boards can be connected to each
output module. A relay board is directly connected to the output module (J1 connector) and a
second relay board is connected to the former.
Esempiocollegamento
/ Connectionexample
Fig. 2.4.1) Relay board and connection to the output module
2.4.2) ST.G/IN8-S and ST.G/OUT16-S module addressing
STG/IN8-S and STG/OUT16-S modules are addressed using the two rotary switches in
RSW 1 and 2 hexadecimals. Rotary switches permit hexadecimal settings (base 16).
Each switch as 16 positions (0-F) and the pointer is positioned on the number chosen
using a screwdriver to create a decimal value between 1 and 255 (see table 1). See the
summary table in para. X for the maximum number of connectable modules to the gas
control unit. 1) INTRODUCTION
Each module must have univocal address in the system. Dual addresses are not
permitted even if modules are on different serial buses.