Niveaurelais NS20

Level Monitor for conductive liquids, 1 Niveau, 1 oder 2 Limits,  MIN / MAX-control, adjustable sensitivity, Housing Design V2 for circuit-breaker-box

Niveaurelais NS20

Part number

Product description

 

Level-Relays NS 20 for conductive liquids can be used as monitors for 1 Level and for controlling a level between 2 electrodes.

  • 3 elektrodes for MIN/MAXcontrol
  • 2 elektrodes (E2 open) as level monitor
  • Sensitivity adjustable 5 kΩ…250 kΩ
  • LED for state of relay
  • Function of relay reversible (picks up or releases at top electrode)
  • Switching-delay adjustable 0,1…10 s
  • Housing 35 mm wide, mounting height 55 mm
  • Universal supply-voltage AC/DC 24-240 V

Application level monitor

Protection from running dry or overflow, monitoring of pumps for leaks, detection of leaks.

Application Min/Max

Controlling a level between minimum (elektrode E2) and maximum (E3). As long as E3 is dry, a magnetic valve is opened (or a pump is running) and liquid is influenting. As soon as maximum (E3) is reached, the NS 20 closes the valve. When the level falls below E2, the cycle starts new. In reverse also discharging of a container can be controlled.

Overview of functions example filling with 2 electrodes

The detection of the level is made with a DC-free measuring of resistance between all electrodes The common electrode in E 1. A magnetic valve that is switched with relay-contacts 15-18 opens and lets liquid in until the upper electrode E3 is in contact with the liquid. Then the relay releases (15-18 open) and the valve closes. The relay remains released as long as electrode E 2 is in contact with the liquid. When the level falls below E2, the relay picks up (LED Relay on, 15-18 close) and the procedure starts new with opening the valve. Thus thelevel of the liquid is kept between E 1 and E 2.

For monitoring one level only or in applications to protect from running dry or overflow or leak detection, only electrodes E1 and E3 are connected.

 

Technical Data

Supply voltage Us

.......

AC/DC 24 – 240 V    ......    0 / 50 / 60 Hz < 3 W < 5 VA

 

Tolerance

.......

DC 20,4 - 297 V         ......    AC 20 - 264 V

 

Level-electrodes (E1 , E2 , E3)

max. voltage

.......

< 6 Veff

 

max. current

.......

<250 μA

 

Switching point

.......

adjustable app. 5 kΩ ... 250 kΩ

 

Switching point 5 kΩ

.......

max. cable-length 2500 m    ......    max. capacity of cable 500 nF

 

Switching point 250 kΩ

.......

max. cable-length 50 m    ......     max. capacity of cable 10 nF

 

Switch on-/off-delay

.......

0,1...10sec adjustable

 

Tolerance

.......

25%

 

Data of relay (EN 60947-5)

Type of contact

.......

1 change-over-contact (CO)

 

Switching voltage

.......

max. AC 415 V

 

Switching current

.......

max. 6 A

 

Switching power

.......

max. 2000 VA (ohmic load)
max. 120 W bei DC 24 V

 

Rated nominal current Ie for co

.......

3 A AC15 250 V    ......     2 A DC13 24 V

 

Recommended fuse

.......

3,15 A slow ( gL )

 

Contact life mechanical

.......

3 x 107 operations

 

Contact life electrical

.......

1 x 105 operations at 240 V / 6 A
1 x 106 operations at 240 V / 2 A

 

Reduction factor at cosϕ = 0,3

.......

0,5

 

UL electrical ratings

.......

250 V ac, 3 A, general use
240 V ac, 1/4 hp, 2.9 FLA
120 V ac, 1/10 hp, 3.0 FLA
C 300

 

Test conditions (EN 50178 / EN 60 947 safe insulation)

Rated impulse withstand voltage

.......

4000 V

 

Contamination level

.......

3

 

Rated insulation voltage Ui

.......

250 V

 

On-period

.......

100 %

 

Rated ambient temperature range

.......

-20 °C ... +60 °C (EN 60068-2-1 dry heat)

 

Interference resistance

.......

EN 61000-6-2

 

Interference transmission

.......

EN 61000-6-3

 

Vibration resistance (EN 60068-2-6)

.......

2…25 Hz ±1,6 mm
25 ... 150 Hz 5 g

 

Housing

Design

.......

V2

 

Mounting height

.......

55 mm

 

Dimensions (B x H x T)

.......

each 1 x 4 mm2

 

Stranded wire with wire-end sleeves

.......

each 1 x 2,5 mm2

 

Protection housing

.......

IP 30

 

Protection terminals

.......

IP 20

 

Attachment

.......

Snap-mount on DIN-rail 35 mm according to EN 60 715 or screws M4

 

Weight

.......

app. 130 g