Sens SG-A1, User Manual

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SENS.413347.015RE
30
PRE A L = 5 C
Address
(0-127)
Command
0x10 CRC
Parameter value
1 byte
Prefix
1 byte 1 byte
Data
length
1 byte
STATE VALUE
Status byte
Parameter
code
Control
checksum
1 byte 1 byte 3 bytes 1 byte
Figure 8.6 - Example of status packet with enabled burst mode (0x10 (16) Concentration, %
LFL as example)
With enabled burst mode, the time for sending packet to automation controllers is
reduced.
Period of sensors network interrogation is determined by number of SENS devices in
SENS line and is calculated using formula if burst mode is disabled:
 
, 560 191 72 600 ms D A S D T
       
where D - number of sensors (gas detectors SENS SG-A1, temperature sensors SENS
PT, pressure sensors SENS PD, etc.);
S - number of displaying (not hibernated) instruments (signaling devices MS-K-500-...);
A - number of adapters (LIN-RS232, LIN-RS485, LIN-USB and etc.).
Note - Specified value of T is maximal, real response time - 0...T. Number of signaling
devices is considered to be equal to one, regardless of their number in SENS line, if signaling
devices are configured for "hibernation" mode.
With enabled burst mode, coefficient of variable D in formula changes:
 
, 560 191 136 600 ms A S D T
      
For example, SENS system has 10 gas detectors SENS SG-A1, one multi-channel
signaling device MS-K-500-3 and one adapter LIN-RS485/232.
Full period (T), with disabled burst mode, is determined:
 
. 20 10 2 2
; 2 2071 1 560 1 191 10 72 600
s n s Cycle
s ms T
    
        
Full period (T), with enabled burst mode, is equal to:
 
. 7 , 2
; 7 , 2 2711 1 560 1 191 10 136 600
s Cycle
s ms T

        
Thus, a considerable gain in time is achieved for data exchanged with automation
controller. 20 s with disabled burst mode, 2.4 s with enabled burst mode.
Burst mode is used in systems without VS-5 sirens and relay units BK-... . Or in system
with requirements for signaling triggering Tsrab = Tkontr.
Tsrab - triggering time with disabled burst mode.
Tkontr - time of controller triggering using relay.
Viewing of selected variable is available for operation modes with "user" and
"administrator" access level.
To set required number of parameter, "administrator" access level is required.
Setting is performed as follows:
- enter configuration menu;
- run calibration command
C231 (enter administrator mode);
- select SEtt menu item;
- assign parameter nP a required value;
- scroll to End item and exit with saving parameters;
- run command C230 (exit administrator mode).