Sensor Electronics SEC Millenium Series Instruction And Operation Manual page 140

Internal Holding
Register Register
Address Address
x = sensor number, or
0 to apply to all sensors.
*The real value must be multiplied by the Gas Factor (2x08).
i.e. 2.12 ppm to set low set point register: scaled low set point = 2.12 X 10 (from 2x08) =
212 (00D4 Hex). When the password is added (4000 Hex) the complete value needed to
write the register and change the low set point then is 40D4 Hex.
**Sensor Float parameters (low, mid and high set points and calibration values) must be
written in sequence in at least one multiple item write operation, starting in order with the
enable password register, high word then low word. These values are IEEE 754 encoded
32-bit values split into two 16-bit words. Upon a complete write of the triad, the value is
saved internally.
***Zone ID (2010/42011) and Self Test (2039/42040) may be written in region 0 (apply
to all sensors) when a SEC 3120 is in either "Identical" or "Unique" sensor roles (unlike
set point or threshold registers where the sensor role must be "Identical"), however if in
the "Single" sensor role, an exception message will be transmitted to the master. If sensor
role is "Identical", values must also be identical!
Internal Holding
Register Register
Address Address
2911 42912
2912 42913
2913 42914
2914 42915
2915 42916
2916 42917
2917 42918
2918 42919
SEC 3120 16-bit Modbus Manual
For Version 1.2 and above
Function Code 16- Write Multiple Sensor Registers
(Data bits and Parameter Specifics)
Function Code 16- Write Multiple Unit Registers
(Data bits and Parameter Specifics)
New 3120 Unit Clock Month Value.
4000 Hex must be added as a password to write value.
New 3120 Unit Clock Day Value.
4000 Hex must be added as a password to write value.
New 3120 Unit Clock Year Value.
4000 Hex must be added as a password to write value.
New 3120 Unit Clock Hours Value.
4000 Hex must be added as a password to write value.
New 3120 Unit Clock Minutes Value.
4000 Hex must be added as a password to write value.
New 3120 Unit Clock Seconds Value.
4000 Hex must be added as a password to write value.
Set New 3120 Unit Clock NOW (00FF Hex set, 0 clear).
4000 Hex must be added as a password to write value.
Bit-mapped Diagnostics Force Coils And Toggle LEDs.
Bit 0: Force low relay coil (1 = on, 0 = off)
Bit 1: Force mid relay coil (1 = on, 0 = off)
Bit 2: Force high relay coil (1 = on, 0 = off)
Bit 3: Force fault relay coil (1 = on, 0 = off)
Bit 4: Toggle LEDs red/green ( 1 = on, 0 = off)
Duration of force will be approximately 30 seconds unless
re-written.
4000 Hex must be added as a password to write value.
Page 39 Of 46
December 2012
Sensor Electronics Corporation
P/N 1580282, Rev. 1, 20121228