Flowserve NRS 2-40 - Manual (Page 8)

8
Function
At regular intervals the level electrode type NRG 26-40 sends a data telegram to the
level switch NRS 2-40. The data transfer is effected by means of a CAN bus according
to DIN ISO 11898. The transferred measuring data are then evaluated and assigned
to the manually adjusted switchpoints. To guarantee the correct functioning and safety
of the system the data transmitting cycle is constantly monitored by the level switch.
When the CAN bus line is interrupted the level switch sends a visual signal to indicate
a malfunction and the relays 1 and 4 will be instantaneously de-energized (alarm
position).
Additional functions, e.g. (de)-energizing delay times of the output relays
(1 to 25 sec.) can be adjusted with the control terminal and display unit URB 1.
Explanatory Notes
Scope of supply
NRS 2-40
1 Level switch type NRS 2-40 (plug-in unit in plastic case with box terminals)
1 Terminating resistor 120
Ω
1 Operating manual
Description
Use level switch type NRS 2-40 in combination with level electrode type
NRG 26-40 for level monitoring. The level switch has the following functions:
■ Four liquid levels with one switchpoint each.
■ High-level alarm, low-level alarm, pump ON, pump OFF, with one switchpoint each.
■ Continuous level monitoring within control band defined by two preset limits.
■ Actual-value output 4-20 mA (optional)
■ Contact multiplication by connecting in parallel a second level switch NRS 2-40
without optional actual value output.
The level data are transmitted via CAN-bus from the electrode NRG 26-40 to the level
switch.