Ametek Land 4500 MKIII, User Manual

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B - 17
Model 4500 MkIII Opacity and Dust Monitor
User Guide
Track and hold
The 4-20 mA current loop output can be set to track or hold during
calibration. This function is controlled using the following system parameters
Register 188 - transceiver output
Register 336 - AFU output 1
Register 340 - AFU output 2
Setting the register value = 1 allows the 4-20 mA current loop to track
during the calibration check. This option is required for compliance
applications so that the calibration value can be recorded by the data
acquisition system.
Setting the register value = 2 freezes the 4-20 mA current loop during
calibration, with the output held to the last valid measurement. This option
is appropriate where the signal is being used as part of a process control
system where the calibration reading could affect the operation of the
controller.
Averaging
The 4-20 mA current loop outputs are factory set for instantaneous response.
Averaged outputs can be configured by setting the foillowing Register values
Register 189 - Transceiver Output Averaging enable
Register 339 - AFU Output 1 Averaging enable
Register 352 - AFU Output 1 Averaging enable
Setting parameter value = 0 disables averaging
Setting parameter value = 1 enables averaging
Register 190 - Transceiver Output Averaging time in minutes
Register 340 - AFU Output 1 Averaging time
Register 353 - AFU Output 1 Averaging time
To set AFU output for 6-minute averaging, set parameter 352 to value 1 and
set parameter 353 to value 6.
Note that the averaging function uses block averages. Therefore, the
instrument measures the opacity for the first averaging period, then it
outputs that value during the second averaging period
B4.11 Setup AFU Alarms
1) Use the and arrows to select AFU Settings and press
2) Use the and arrows to select Alarm 1 Type and press
3) Use the and arrows to select Opacity , Optical Density or
Dust Density and press
4) Use the and arrows to select Alarm 1 Level and press
5) Use the and arrows to change the Alarm Level and press
6) Set up Alarm 2 in a similar manner.
7) Press to return to Settings