VorTek U44 Series, Инструкция по эксплуатации

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Series U44 Instruction Manual
M-000-00090
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4.5 System Lock
System lock is intended to prevent operation error due to tampering by unauthorized personnel.
The Password Menu 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.
4.6 Active 4 - 20 mA 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 - 20 mA or 0 - 20 mA selected in the Output Menu. For details, please refer to the
Output Menu in "Display & Menus".
In Output Menu – 4 mA Output – 4 mA, enter a 4 mA flow value. Enter the 20 mA flow value in Output Menu – 4
mA Output – 20 mA. For example, if the flow range in a specific pipe is 0 ~ 1000 m
3
/h, enter 0 and 1000 in Output
Menu – 4 – 20 mA Output. If the flow ranges from -1000 ~ 0 ~ 2000 m
3
/h, configure the 20 - 4 - 20 mA output by
selecting in Output Menu when flow direction is not an issue. Enter 1000 in Output Menu – 4 mA Output – 4 mA
and 2000 in Output Menu – 4 mA Output – 20 mA. When flow direction is an issue, module 0 - 4 - 20 mA is
available. When the flow direction displays as negative, the current output is in range of 0 - 4 mA, whereas the 4 -
20 mA is for the positive direction. The output module options are displayed in the Output Menu.
Calibrating and testing the current loop is performed in Output Menu – 4 - 20 mA Output. Complete the
steps as follows:
Use < and > to switch menus. Select the 4 mA or 20 mA outputs by pressing ENTER, connecting an
ammeter to test the current loop output and calculate the difference.
4.7 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 to the user’s
actual requirements.
For example: if a pipe flow range is 0 ~ 5000 m
3
/h, the relative frequency output required is 100 ~ 1000 Hz, and the
configuration is as follows:
In Output Menu – Scaled Frequency – Min Hz (lower limit frequency output flow value), input 0;
In Output Menu – Scaled Frequency – Max Hz (upper limit frequency output flow value), input 5000;
In Output Menu – Scaled Frequency – Max Frequency (frequency range), input 1000;
Typical Open Collector Transistor (OCT) Output wiring diagram as below: