Nivobob
®
1
2
3
4
5
6
7
8
9
10
11
12
NB 3000
gi130109
22
Continuous level measuring system
NB 3000
Technical information / Instruction manual
page G
Signal overview
Signal input:
Start of measurement
• Floating contact (terminal 24, 25) or
• 24 V DC voltage (terminal 25, 27), current consumption approx. 25mA, observe the polarity.
Duration of starting signal: 0.7 to 5s
The contact must be closed or the 24V signal must be present to start.
Measurement interruption
Used to avoid a measurement in case of filling and to interrupt a running measurement when filling starts.
When the terminal 24 und 26 are opened, the sensor weight returns to the upper stop position.
If required, remove factory provided wire between terminal 24 and 26 and connect to the filling coupling.
The contact must be closed to enable a measurement.
Signal input:
Full detector
Enables to implement a full detector signal in the Modbus or Profibus.
When the signal is present (terminal 24-28 closed) the yellow LED next to the display in on.
Signal output:
0/4-20mA
Programmable to indicate a level or a volume signal. The output is updated, when the sensor weight touches
the surface of the bulk good. It stays until the next measurement is done.
Signal output:
Relay
Relais can be setted as shown in the following table:
Relay 1
Relay 2
Relay 3
Relay 4
Factory settings
Counting pulse
Reset pulse
Failure
Upper stop position
Programmable
Limit switch 1
Limit switch 2
Maintenance
Maintenance
Relais 1/2 set to Counting/Reset pulse:
The counting pulse output is used to connect an external digital counter or a PLC with counting input.
Reset pulse
(terminal 6 and 7):
After start of measurement, a reset pulse is given. It is used to reset the connected evaluation device
(counter/ PLC, ...).
Counting pulse
(terminal 5 and 6):
The counting pulse communicates the measured value to the connected evaluation device. During the
downward movement of the sensor weight, this pulse is generated according to the following table:
Relais 1/2 set to Limit switch:
It is possible to indicate two independent level limit switches. The limit switch signal is derivated from the
analogue measurement signal (details see Programming page 27)
Relay 3 - set to "Failure"
The relay indicates a failure (see also programming on page 28 and diagnostics "Failure" on page 39)
Relay 3 - set to "Maintenance"
The relay indicates a necessary maintenance (see also programming on page 28 and diagnostics
"Maintenance" on page 37)
Start
Reset
Counting
Timing
Signal input / output
Counting pulse
programmed to:
ON
OFF
10cm (1/6ft) / pulse
0.13s
0.13..0.3s
5cm (1/3 ft) / pulse
0.07s
0.07..0.15s
