Technical data
Supply voltage
24 VDC, + / –20 %
Fuse
external semi-delay M0.5A
Power consumption
5W
Connecting the level electrode/level transmitter
(selected by switch)
1 input for NRG 21-.. and NRG 26-21 level electrode, 3-pole with shield, or
1 analogue input 4-20 mA, e.g. for NRGT 26-. level trans- mitters, 2-pole with shield.
Supply voltage to level electrode
12 V DC
Input/output
Interface for data exchange with the URB 55 visual display and operating unit
Inputs
1 analogue input, potentiometer 0 – 1000 Ω,
2-wire connection
(indication of valve position, NRR 2-52 only)
1 analogue input 4-20 mA (steam flowrate) (optional)
1 analogue input 4-20 mA (feedwater flowrate) (optional)
Outputs
NRR 2-52:
2 volt-free changeover contacts,
8 A 250 V AC / 30 V DC cos φ = 1 (control valve). 2 volt-free changeover contacts,
8 A 250 V AC / 30 V DC cos φ = 1,
OFF delay: 3 seconds (MIN/MAX alarm)
NRR 2-53:
4 volt-free changeover contacts,
8 A 250 V AC / 30 V DC cos φ = 1,
OFF delay: 3 seconds (MIN/MAX alarm)
1 analogue output 4-20 mA, max. load 500 ohms (manipulated variable Y)
Inductive loads must have interference suppression
(RC combination) as per the manufacturer’s specification.
NRR 2-52, NRR 2-53:
1 analogue output 4-20 mA,
max. load 500 ohms (actual value)
Indicators and controls
1 multicolour LED (start-up = amber, power ON = green, communication failure = red)
1 4-pole code switch for configuration.
Housing
Housing material, base: black polycarbonate;
front: grey polycarbonate, grey.
Terminal strips can be removed separately.
Housing attachment: Mounting clip on support rail TH 35, EN 60715.
Electrical safety
Pollution degree 2.
IP rating
Housing: IP 40 to EN 60529 Terminal strip: IP 20 to EN 60529
Weight
Approx. 0.5 kg
Ambient conditions:
Ambient temperature
when system is switched on 0 ° … 55 °C in operation –10 … 55 °C
Transport temperature
–20 … +80 °C (< 100 hours), only switch on after a defrosting period of 24 hours.
Storage temperature
–20 … +70 °C, only switch on after a defrosting period of 24 hours.
Relative humidity
max. 95%, non-condensing
