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NIVOCONT K
KRK–622
1. APPLICATION 2.3 ACCESSORIES
The conductive measuring principle can be applied to liquids with specific conductivity over – User’s Manual CONDUCTIVE LEVEL SWITCH
10 μS/cm. The switching unit can sense the resistance between probes. Conductivity measure- – Warranty Card
– EU declaration of conformity USER’S MANUAL
ment is suitable only for detecting the presence of liquid at a given level of the tank. This level
is represented by the length of the probe. – Seal (2 mm [0.08"] thick)
The level switch consists of a NIVOCONT KRK–622– type switching unit and the (KLINGER OILIT):
KLN–2 type probes selected according to the task. Probes are to be connected to the 1× ⅜" (KSP–201, KSS–201, KSN–201)
NIVOCONT KS– 0 type probe socket head that can be screwed into the tank. 1× 1½" (KSH–20)
If the material of the tank or its internal insulation is not conductive then a reference probe – M6 nut (standard SW):
should be used in addition to the one, two, three or four probe(s), if the material of the tank is 3× (KSH–202)
conductive, the tank can be used as a reference probe. 4× (KSH–203, KSH–204)
The conductive switch is suitable for filling-emptying control with 2 relay outputs working simul- – M6 nut (non-st. SW)
taneously or for level detection of 2 independent levels (in 1 or 2 tanks) with 2 independent relay 1× (KSH–204) PDF 
outputs. More level switches can also be used with one common reference probe ‘C’ using any
Manufacturer:
combination of multiple-probe and single-probe socket. NIVELCO Process Control Co.
H–1043 Budapest, Dugonics u. 11.
Tel.: +36-1-889-0100  Fax: +36-1-889-0200
2. TECHNICAL DATA E-mail: sales@nivelco.com  www.nivelco.com
2.1 GENERAL DATA 2.1.2 Probe sockets
2.1.1 Switch
KSK– KSP– KSS– KSN– KSH– KLN– KLP– KLP–
KRK–622–1, –2 KRK–622–4 201 201 201 201 202 203 204 301 302 303 304 2 201 204
Probe voltage max. 3.5 V AC Number of probes 1 2+r 3+r 4+r 1+r 2+r 3+r 4+r 1 –
Probe current < 1 mA AC Insulation of socket ABS PP PFA PP –
Sensitivity Adjustable: 5…100 kΩ M4 nut, M20x1.5
Cable gland Pg7(1) – –
protected by a rubber cap cable diameter Ø6…12 mm (Ø0.25…0.5 inch)
800 nF (sensitivity 5 kΩ)
Max. cable capacitance Process conn. – ⅜" BSP 1½" BSP M6 –
100 nF (sensitivity 100 kΩ)
A44 KO35 KO35
Response time max. 400 ms Socket material – PP PP –
c. steel stainless steel (1.4571) 1.4571
Mechanical accuracy ±5% Powder-coated
Housing material – PBT – PP PVDF
Delay Adjustable: 0.5…10 s cast aluminum

Relay output 2× SPDT max. max.

Medium max. +80 °C
max. +200 °C (+391 °F) max. +80 °C (+176 °F) – +80 °C +130 °C
Switching voltage 250 V AC1, 24 V DC temperature (+176 °F)
(+176 °F) (+266 °F)
Switching current 16 A AC1 3 bar
Max. pressure – 16 bar (232 psi) 3 bar (43.5 psi) –
Switching power 4000 VA AC1, 384 W DC (43.5 psi)
Min. output power DC 4 kV (power – output) Ingress protection – IP20 IP65 IP67 –
Mechanical life-span 3 × 107 switches Mass
50 g
100 g (0.22 lb) 400 g (0.88 lb)
220 g/m
–
Electrical life-span 0.7 × 105 switches (0.11 lb) (0.13 lb/ft)
r = reference probe  (1)
cable: Ø4…7 mm
230 V or 110 V AC 24 V AC/DC
Power supply Un
Galvanically separated (AC 50/60 Hz) 2.2 ORDER CODES (NOT ALL CODE VARIATION AVAILABLE)
Voltage range allowed Nominal voltage –15%…+10%
Power consumption
2.5 W / 5 VA (230 V AC, 110 V AC), KRK–622–  NIVOCONT KS  – 0
1.4 W / 2 VA (24 V AC/DC) Power supply Code
Ambient temperature –20…+55 °C (–4…+131 °F) Type Code Housing mat. Code Probe number Code
230 V AC 1
Electrical connection max. 2.5 mm2 (AWG14) Cable probe K Aluminum 2 1 + reference probe* 1*
110 V AC 2
Overvoltage category II SINGLE PROBE Plastic 3 2 + reference probe 2
24 V AC/DC 4
Pollution degree 2 PP socket P 3 + reference probe 3
Electrical protection Class II Class III KLN–2  Carbon steel socket S 4 + reference probe 4
Ingress protection IP20 Stainless steel socket N *only plastic version

Mechanical connection DIN EN 60715 rail Code Probe length Code MULTIPLE PROBES
Stainless steel socket H Separator:
Weight 248 g (0.55 lb) 147 g (0.32 lb) 0 0m 0m 0
NIVOCONT KLP–201 – for plastic version
1 1 m (3.3 ft) 0.5 m (1.64 ft) 5 NIVOCONT KLP–204 – for aluminum version
2 2 m (6.6 ft)
3 3 m (10 ft)
2.4 DIMENSIONS

Pg7

M20x1.5
SW55
⅜" BSP

Switch Cable Probe Probe Socket Probe Socket Probe

KRK–622– KSK–201 KSH–20 KSP–201 / KSS–201 / KSN–201 KLN–2

Uninsulated base probe

M20x1.5
85

Probe Socket Separator Probe Socket Separator

KRK–512– KLP–204 KSH–30 KLP–201
krk622en1905h ♦ page 1
3. INSTALLATION Example of setting DIP switch:
A KRK–622– switching unit can be mounted on DIN EN 60715 rail. Select the desired function in accordance with the figures. The upper 3 switches are for select-
It is recommended the KLN–2 type probes to be cut to the length required for level detec- ing the number of the function you want to use. If you want to use Function 5 you should set
tion on site. The probes should be screwed into the KS–0 type sockets. the switches as follows: set the 1st switch to the right, the 2nd to the left and the 3rd to the left.
Then select whether you need ON delay or OFF delay with the 4th switch. You can choose the
ALWAYS REMEMBER TO TIGHTEN THE PROBE WITH AN M6 NUT! type of delay, but you cannot deactivate the delay. However, the minimum delay time you can
When using KSH–204 type probe sockets the reference probes should be tightened with spe- set with the potentiometers is 0.5 seconds.
cial SW hexagonal M6 nuts! The DIP switch looks like this after setting function 5 with an OFF delay:
It is suggested KLP–201 or KLP–204 type PVDF separators (suitable up to +130 °C) to be
used at every 0.5 m for multiple probe devices to keep the probes apart.
A KSK–201 single probe, attached to an insulated cable, can be lowered into pits and wells 1st switch to right 1, 2, 3, 4 5, 6, 7, 8
without running the risk of a short circuit. When a detection is needed in a well or in a plastic
2nd switch to left Function 1, 2, 5, 6 3, 4, 7, 8
pipe 2 of them have to be used. For additional levels additional probes should be used.
3rd switch to left 1, 3, 5, 7 2, 4, 6, 8
4. WIRING
If the wall of the tank is conductive no reference probe is needed. In this case terminal ‘C’ To off delay switch to right ON Delay OFF Delay
has to be connected to the tank.
On multiple probe units ‘E1’ and ‘E2’ are marked with 1–4, the reference probe is marked
5.2 FUNCTIONS
with ‘C’. Admissible length of cable between switching unit and probes depends on cable
Attention! The following wiring diagrams show the wiring of the KRK–622–4,
capacitance and conductivity.
24 V supply voltage device.
The terminal block assignment of KRK–622–1 and KRK–622–2 is not the same, the
Functions 1 to 4 are for controlling 2 pumps according to the following picture:
KRK–622–4 is different. There is no ‘S’ terminal at the KRK–622–1 and KRK–622–2. Refer-
ring to the illustration below for the terminal block assignments of the devices.
KRK–622–1, –2 KRK–622–4
Un Un E2 Un
E1
C E2 C C E1
A1 A2 C E2 E1 S

A1 A2 C E2 E1 A1 A2 C E2 E1 S

OUT 1 OUT 2

OUT1 OUT2 OUT1 OUT2 Tank I. 16 15 18 28 25 26 Tank II.

L
16 15 18 28 25 26 16 15 18 28 25 26

Pump 1 Pump 2
A1, A2 – power supply S – shielding
N
C – reference probe 15, 16, 18 – 1st relay output – pump control 1
E1 – max. probe (OUT1) 25, 26, 28 – 2nd relay output – pump control 2 Functions 5 and 6 are for controlling one pump (filling or emptying one tank) and for generating
E2 – min. probe (OUT2) (function 1, 2, 3, 4) or alarm (function 5, 6, 7, 8) alarm signal according to the following picture. If level is not between ‘E1’ and ‘E2’ alarm is
generated:
To eliminate signal interferences it is recommended to use shielded cables to the probes.

5. COMMISSIONING
Un
5.1. ADJUSTMENT
A1 A2 C E2 E1 S
The green LED (Un) shows that the unit is on, the energised state of the relays are indicated by C E2 E1

the OUT1 respectively OUT2 LEDs. If the OUT1, OUT2 (red) LEDs are flashing, they indicate
the timer operation. When they light up, it shows that the corresponding relay is switched max.
on. Yellow LED (FAIL) indicates probe failure (for example at Functions 5 and 6 probe ‘E1’ is
OUT 1 OUT 2
flooded and probe ‘E2’ is not, which is unreal state so the yellow LED is on.) min.

16 15 18 28 25 26 Tank
Operating modes, delay ON and delay OFF can be set with the DIP switch on the front panel.
t1[s] and t 2[s] potentiometers are for adjusting the delay time. The delay value can change L
from 0.5 seconds to 10 seconds. You can set the sensitivity of the two probes independently
using the RE1 or RE2 potentiometers. The sensitivity setting should comply with the conduc-
tivity of the fluid. Do not set sensitivity higher than required because the vapour precipitation Pump Alarm
may lead to operation disturbance. In heavily humid environment insulated probes can be N
used. With the ON Delay / OFF Delay switch on the DIP switch, delay type of the relays can
be selected (switch-on delay or switch-off delay).
DIP switch
Functions 7 and 8 also controls one pump and generates one alarm signal:
(Function 7 is showed on the picture)

Supply voltage
1,2,3,4 5,6,7,8
indication Un Un
Function 1,2,5,6 3,4,7,8
1,3,5,7 2,4,6,8
30 50 ON OFF E2 C A1 A2 C E2 E1 S C E1
20 70 Delay Delay
OUT1 switching Delay adjustment
10
indication 90
for Relay 1
OUT1
5 100

Probe failure RE1[kΩ] t1[s] OUT 1 OUT 2

FAIL 30 50 Delay adjustment Tank
16 15 18 28 25 26
for Relay 2
20
OUT2 switching
70
10
indication OUT2 90
L
5 100
RE2[kΩ] t2[s]
KRK–622

2 rotary potentiometers for adjusting the Pump Alarm

sensitivity for E1 and E2 probes independently Well
according to the conductivity of the fluid Reservoir
N

Front panel of NIVOCONT KRK–622

krk622en1905h ♦ page 2
FUNCTION 1 FUNCTION 5 – PUMP UP (FILLING), ON DELAY:
Controlling level in 2 separate tanks (each with 1 probe) – filling. The pumps are running and
fill the tanks until the levels reach the corresponding probes (E1 or E2). probe H
Relay 1 (E1): Pump control 1
probe D
Relay 2 (E2): Pump control 2 tH
LED H
FUNCTION 2 tD tD
Controlling level in 2 separate tanks (each with 1 probe) – emptying. The pumps are running LED D

and emptying the tanks until probes are flooded. relay 15-18
Relay 1 (E1): Pump control 1 relay 25-28
Relay 2 (E2): Pump control 2
FUNCTION 3 FUNCTION 5 – PUMP UP (FILLING), OFF DELAY:
Controlling level in 2 separate tanks (each with 1 probe). Pump 1 is emptying the tank and
stops when probe ‘E1’ is not flooded anymore. Pump 2 is filling the tank and stops if level probe H
reaches probe ‘E2’. probe D
Relay 1 (E1): Pump control 1 LED H
tH

Relay 2 (E2): Pump control 2 tD tD

LED D
FUNCTION 4
relay 15-18
Controlling level in 2 separate tanks (each with 1 probe). Pump 2 is emptying the tank and
stops when probe ‘E2’ is not flooded anymore. Pump 1 is filling the tank and stops if level relay 25-28

reaches probe ‘E1’.

Relay 1 (E1): Pump control 1 FUNCTION 6 – PUMP DOWN (EMPTYING THE TANK), ON DELAY:
Relay 2 (E2): Pump control 2
probe H
FUNCTION 5
probe D
Both probes and reference probe are in one tank. Relay 1 controls the pump, which keeps tH
the tank filled and maintains the level between probes ‘E1’ and ‘E2’. Relay 2 is used to alarm LED H
tD tD
signalling. Relay 2 is on if the level is not between the two probes. LED D
Relay 1 (E1): Pump control 1 relay 15-18
Relay 2 (E2): Alarm
relay 25-28
FUNCTION 6
Both probes and reference probe are in one tank. Relay 1 controls the pump, which keeps FUNCTION 6 – PUMP DOWN (EMPTYING THE TANK), OFF DELAY:
the tank empty and maintains the level between probes ‘E1’ and ‘E2’. Relay 2 is used to
alarm signalling. Relay 2 is on if the level is not between the two probes. probe H
Relay 1 (E1): Pump control 1 probe D
Relay 2 (E2): Alarm tH
LED H
FUNCTION 7 LED D
tD tD

Pumping from well to the tank – probe ‘E2’ is in the well, probe ‘E1’ is in the tank. The pump
relay 15-18
only runs if probe ‘E2’ is flooded (enough water in the well) and the tank is not full meaning
relay 25-28
the level does not reach probe ‘E1’. The alarm reports a lack of water in the well (probe ‘E2’
is not flooded).
FUNCTION 7 – PUMP FROM WELL TO TANK, ON DELAY:
Relay 1 (E1): Pump control 1
Relay 2 (E2): Alarm probe H (tank)
FUNCTION 8 probe D (well)
Pumping from reservoir to the tank – probe ‘E2’ is in the reservoir, probe ‘E1’ is in the tank. LED H
tH tH
The pump only runs if probe ‘E2’ is flooded (full reservoir) and the tank is not full (probe ‘E1’).
LED D
The alarm reports the status of full tank and reservoir (both probes are flooded).
Relay 1 (E1): Pump control 1 relay 15-18 (Pump)

Relay 2 (E2): Alarm relay 25-28 (Alarm)

5.3 TIME DIAGRAMS FUNCTION 7 – PUMP FROM WELL TO TANK, OFF DELAY:
FUNCTION 1, 3, 4 – PUMP UP (FILLING), ON DELAY: probe H (tank)

probe D (well)
probe tH
t LED H
LED LED D
tD

relay relay 15-18 (Pump)

relay 25-28 (Alarm)

FUNCTION 1, 3, 4 – PUMP UP (FILLING), OFF DELAY: FUNCTION 8 – PUMP FROM RESERVOIRS TO TANK, ON DELAY:

probe H (tank)
probe
t probe D (reservoirs)
LED LED H
tH tH

relay LED D

relay 15-18 (Pump)

FUNCTION 2, 3, 4 – PUMP DOWN (EMPTYING), ON DELAY: relay 25-28 (Alarm)

probe FUNCTION 8 – PUMP FROM RESERVOIRS TO TANK, OFF DELAY:

t
LED probe H (tank)

probe D (reservoirs)
relay tH
LED H
tD
LED D
FUNCTION 2, 3, 4 – PUMP DOWN (EMPTYING), OFF DELAY:
relay 15-18 (Pump)

relay 25-28 (Alarm)

probe
t
LED
relay

krk622en1905h ♦ page 3
6. MAINTENANCE AND REPAIR
The device does not require regular maintenance. The warranty card contains the
terms and conditions. Before returning the device for repairs, it must be cleaned
thoroughly. The parts in contact with the medium may contain harmful substanc-
es; therefore, they must be decontaminated. Our official form (Returned Equipment
Handling Form) must be filled and enclosed in the parcel. Download it from our
website www.nivelco.com. The device must be sent back with a declaration of de-
contamination. A statement must be provided in the declaration that the decontam-
ination process was successfully completed and that the device is clean from any
hazardous substances.

7. STORAGE CONDITIONS
Storage temperature: –30…+70 °C (–22…+158 °F)
Relative humidity: max. 85%.

krk622en1905h
December 2019
NIVELCO reserves the right to change technical data without notice.

krk622en1905h ♦ page 4