FD TMS, Инструкция по установке и эксплуатации

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5 Current settings
Current output model: 4~20mA and fixed current.
When the "Fixed current" is selected, the output currrent is fixed in a
given value.
For example: the current output model is set to "4~20mA"
When there is no flow, if the output is measured as 3.89mA with a
multimeter, then set the " Adjust Iout Zero " to 3.89mA
At the maximum flow rate, if the outpout is measured as 19.75mA
with a multimeter, then set the " Adjust Iout Zero " to 19.75mA
Calibrate the cuurent output with "Fixed current" model:
Setp 1: Connect a multimeter to the current output circuit
Setp 2: Set the current output model to "Fixed current"
Step 3: Move the ">" cursor to next row, enter the setting model by pressing Ent key. Select the output
current value by pressing Page Down Key. Select the value to 4mA.
Step 4: Check the multimeter reading, if it's not 4mA (for example, 3.90mA), press Page Down Key to
enter the calibration menu. Move the ">" cursor to " Adjust Iout Zero " and then press Ent Key to edit
the value. Enter 3.90mA(in this example) and then press Ent Key angain to save.
Step 5: Hold down the Shift Key and Page Down Key at same time to return to previous menu. Select
the 20mA and press Ent Key.
Step 6: Check the multimeter reading, if it's not 20mA (for example, 19.90mA), press Page Down Key
to enter the calibration menu. Move the ">" cursor to " Adjust Iout Span " and then press Ent Key to
edit the value. Enter 19.90mA(in this example) and then press Ent Key angain to save.
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6 Alarm Settings
Set the upper alarm and lower alarm. The alarm setpoints are always
expressed in percentage of instrument full scale . For instance,
setting the Lower alarm setpoint to 10% means:
The lower alarm setpoint =(upper span - lower span)*10%.
At the example left, both upper anf lower hysteresises are set to 0.5.
That means,:
the switch back point of upper alarm = upper alarm setpoint - upper
hysteresis(i.e. 8-0.5)
the lower alarm switch back point = lower alarm setpoint + lower
hysteresis(i.e. 2+0.5)