LRF-3000S Ultrasonic Transit-time Flow meter
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5.5.
System Lock
System lock is intended to prevent operation error due to tampering by unauthorized personnel.
M54 is for system lock, unlock it by using the selected password only. If "lock” is displayed on the screen, then
enter the correct password.
Keep the password in mind or recorded in a safe place, otherwise the instrument cannot be used.
5.6.
4 ~ 20mA Current Loop Output
With a current loop output exceeding an accuracy of 0.1%, the flow meter is programmable and configurable with
outputs such as 4 ~ 20mA or 0 ~ 20mA selected in Menu 32. For details, please refer to Menu 32 in "Window
Display Explanations".
In Window M32- Range- LowL, enter a 4mA flow value. Enter the 20mA flow value in Window M32-
Range-UpperL. For example, if the flow range in a specific pipe is 0 ~ 1000m
3
/h, enter 0 in Window M32 and
1000 in Window M32. If the flow ranges from -1000 ~ 0 ~ 2000m
3
/h, configure the 20 ~ 4 ~ 20mA output by
selecting in Window M32 when flow direction is not an issue. Enter 1000 in Window M32 LowL and 2000 in
Window M32 UpperL. When flow direction is an issue, module 0 ~ 4 ~ 20mA is available. When the flow
direction displays as negative, the current output is in range of 0 ~ 4mA, whereas the 4 ~ 20mA is for the positive
direction. The output module options are displayed in Window M32.
Calibrating and testing the current loop is performed in Window M32-Check. Complete the steps as follows:
Use “
↑
” and “
↓
” to switch. "check 4mA", "check 8mA", "check 16mA", "check 20mA" readings, connect an
ammeter to test the current loop output and calculate the difference. Calibrate the 4-20mA is in M62.
5.7.
Frequency Output
The flow meter is provided with a frequency output transmitter function. The high or low frequency output
displayed indicates the high or low flow rate reading. The user can reset the frequency output as well as flow rate
as the user’s actual requirements.
For example: if a pipe flow range is 0 ~ 5000m3/h, the relative frequency output required is 100 ~ 1000Hz, and
the configuration is as follows:
In Window M33-Range-LowerL (lower limit frequency output flow value), input 0;
In Window M33-Range -UpperL (upper limit frequency output flow value), input 5000;
In Window M33-Mode-Frange( frequency range), input 100
、
1000;
In Window M33-Mode-Option, select “a.Flow Rate”;
Typical OCT Output wiring diagram as below:
