NOVUS AUTOMATION
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Electrical Connection
Input
Output
1
ALARM
2
OUT (Retransmission)
3
GND
Power Supply
4
NC
5
POWER
6
GND
RS485
See table below.
Electrical connections
The table below helps you connect the RS485 communication interface connectors:
Bi-directional data line.
Terminal 7
Inverted bi-directional data line.
Terminal 8
Optional connection that improves communication performance.
Terminal 9
RS485 connections
4.2.4
USB CONNECTION
The USB connection is used exclusively for the device diagnosis and configuration. The USB interface is on the
NP785 Ultra Low Differential
Pressure Transmitter
side.
It is recommended that the device be configured before it is attached to the DIN rail.
For more information, see
chapter.
Figure 6 –
USB Cable connection
4.2.5
AUTO-ZERO KEY
You can use the Auto-Zero function to automatically reset the sensor by pressing the key located next to the USB interface for more than 2
seconds. If the pressure read from the sensor is within the allowable range (see
Table 10
), the sensor reading will be reset to zero.
You can also perform this function through the
NXperience
software (see
section of the
chapter). For more
information about the Auto-Zero function, see
chapter.
You can also define in the software whether the Auto-Zero function will reset the User Offset. By factory default the Auto-
Zero function does not change previous Offset settings.
4.2.6
DIAGNOSTIC LED
This LED is used to perform a diagnosis during the operation of the device. When turning the device on, the LED will remain on for about 3 seconds
and will flash in the following circumstances:
•
LED on: The device is operating correctly, within the configured limits.
•
LED flashing slowly: An alarm is triggered.
•
LED flashing quickly: The measured pressure is outside the configured relay limits.
•
One long flash: The Auto-Zero function has been performed successfully.
•
Three short flashes: The Auto-Zero function was not performed.
•
LED off: There was an error in the device.