Carel GDWBI20A00, User Manual

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22
ENG
+0300046IE - rel. 1.3 - 05.01.2022
Response time
The response time T50 or T90 (in seconds) is the time taken to reach 50%
or 90% respectively after supplying the target gas at a concentration of
100% of the sensor’s full scale.
T10 is the time needed to return from 100% to 10% of the sensor’s full
scale. Response times are typical values measured under reference
conditions. All response times are expressed in seconds and represent
nominal values.
Type of gas Range
[ppm]
Average response time [s]
T50 T90 T100 T10
(return)
Semiconductor, refrigerant
HFO1234YF 1000 132 348 544 300
HFO1234ZE 1000 154 429 903 363
R134A 1000 240 597 860 612
R32 1000 72 222 473 200
R404A 1000 104 315 495 248
R407A 1000 94 391 676 420
R407F 1000 114 412 732 366
R410A 1000 67 247 483 217
R448A 1000 95 307 544 233
R449A 1000 110 339 552 291
R450A 1000 158 494 844 462
R452A 1000 98 340 601 268
R452B 1000 86 265 539 281
R454A 1000 98 293 592 251
R507 1000 72 238 486 223
R513A 1000 135 411 659 452
R454B 1000 71 223 595 294
R455A 1000 97 262 598 309
NDIR
CO2 10000 28 140 366 150
Electrochemical
(NH3) 100 22 101 413 97
Semiconductor, fl ammable
R290 2500 10 22 98 36
Tab. 5.g
5.4 Modbus registers
5.4.1 Modbus connections
The RS485 port allows communication with the gas detector using the
Modbus-RTU protocol.
Connection symbol Meaning
B -, Rx, inverting signal
A +, Tx, non-inverting signal
GND Earth reference (other than 0 V)
SH Shielded cable connection
Tab. 5.h
5.4.2 Modbus confi guration
The RS485 communication settings can be selected.
Setting Selection Default
Address 1 to 247 1
Baud rate 9600 -19200 baud 19200 baud
Stop bits 1-2 2
Parity None-Odd-Even None
120 Ω termination Enable-Disable Disable
Tab. 5.i
5.4.3 List of variables
04 - Input Registers - R
Register Description Range Unit
100 Gas concentration level (% of full scale) 0 : 100 %
101 Gas concentration level in ppm See the gas
range table ppm
103 Full scale sensor level in ppm ppm
104 Low alarm set point (% full scale) (local) 0 : 100 %
105 Sensor timer 0 : 65,535 hours
106 Detector Modbus address 1 : 247
107 Software version (fi rmware revision) -
108 Machine code (proprietary machine number) 527
109 Order number 300
Tab. 5.j
03 - Holding Registers - R/W
Register Description Range Details
200 High alarm
set point (ppm) See the
gas range table High alarm set point / thresh-
old in parts per million (set
by controller, overwrite local
sensor values)
201 Alarm delay 0 : 15 Buzzer-alarm delay sets the
time (in minutes) that the
buzzer fl ag and alarm fl ag are
activated after the gas con-
centration exceeds the alarm
set point.
202 Buzzer delay
(mapped to
register 201) The values set for reg. 201 and
reg. 202 are always the same
203 Low alarm alarm
set point (ppm) See the gas range
table Low alarm set point / threshold
level in parts per million
Tab. 5.k
02 - Input Status - R
Register Description Range Details
300 High alarm fl ag 0 : 1 1: The gas concentration is greater
than or equal to the high alarm set
point
0: The gas concentration is below the
high alarm set point
301 Relay status 0 : 1 1: One or more relays are active.
0: All relays are inactive
302 Sensor fault 0 : 1 1: Sensor not found or sensor open
circuit detected.
0: Sensor found in the circuit and no
open circuit fault detected
303 Red LED 0 : 1 1: The red LED is on. Alarm/fault
indication.
0: The red LED is off .
304 Green LED 0 : 1 1: The green LED is on.
Warm-up status or normal operation.
0: The green LED is off .
307 Low alarm fl ag 0 : 1 1: The gas concentration is greater
than or equal to the low alarm set
point
0: The gas concentration is below the
low alarm set point
Tab. 5.l
01 - Coils Status - R/W
Register Description Range Details
400 Buzzer fl ag 0 : 1 1: buzzer on
0: buzzer off
401 Test fl ag 0 : 1 1: Sensor on/operating for more than 1
year and requires testing.
0: The sensor does not yet require
testing.
402 Relay contact
behaviour 0 : 1 1: Fault relay operation (see the relay
logic table)
0: Standard relay operation (default)
Tab. 5.m
5.5 Relay logic table
Relay behaviour with relay failsafe operation (register 402)
0: Standard relay operation (default)
1: Relay failsafe operation
This register value will aff ect each relay.
Event cause
0: Standard operation
(default)
1: Failsafe operation
At power on
Relays 1, 2, 3 de-ener-
gised:
NO the output is open
Relays 1, 2, 3 energised:
NO the output is closed
Sensor fault active
Relay 3 energised:
NO the output is closed
Relay 3 de-energised:
NO the output is open
If the gas level exceeds
the low alarm threshold
register 203
Relay 2 energised:
NO the output is closed
Relay 2 de-energised:
NO the output is open
If the gas level exceeds
the high alarm threshold
register 200
Relay 1 energised:
NO the output is closed
Relay 1 de-energised:
NO the output is open
Tab. 5.n