NIVOCONT

2.3 ACCESSORIES

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We are sure that you will be satisfied throughout its use!

KRK - 512 CONDUCTIVE

LEVEL SWITCH

Users manual
Certificate of Warranty
Declaration of Conformity
Sealing (2 mm thick)
(KLINGER OILIT)
1 pc. 3/8 (for KSP-201,
KSS -201, KSN-201)
1 pc. 1 for a KSH-20_
M6 nut (standard SW):
3 pcs. for KSH-202
4 pcs. for KSH-203, KSH-204
M6 nut (non-st. SW):
1pc. for KSH-204

1. APPLICATION
The conductive measuring principle can be applied to liquids with specific conductivity over
10 S/cm. The switching unit can sense the resistance between probes. Conductivity
measurement 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.
The level switch consists of a NIVOCONT KRK-512-5 type switching unit and the
KLN-2 type probes selected according to the task. Probes are to be connected to the
NIVOCONT KS-0 type probe socket head that can be screwed into the tank. If the
material of the tank or its internal insulation is not conductive then a reference probe
should be used in addition to the one, two, three or four probe(s), if the material of the tank
is conductive, the tank can be used as a reference probe.
The conductive switch is suitable for filling / emptying control or level limit.

USER'S MA NUAL

Manufac tu rer
NIVELCO Proc ess Contro l Co.
H-104 3 Buda pest, Du gonics u. 1 1.
Phon e: 88 9-010 0 Fa x: 889 -0200
e -mail: sa les@nivelco.com www.nivelc o.co m

2. TECHNICAL DATA
2.1 GENERAL DATA
2.1.1 TECHNICAL DATA OF THE SWITCHING UNIT
Type

2.1.2 TECHNICAL DATA OF PROBE SOCKETS

KRK-512-5

Probe voltage
Probe current
Sensitivity
Max. cable capacity
Response
Setting accuracy (mech.)
Delay
t1 delay
Relay output
Switching voltage
Switching current
Switching power
Electrical strength
Mechanical life-span
Electrical life-span
Power supply Un

3.5 V AC
< 0.2 mA AC
Adjustable: 5 k ... 100 k
800 nF
max. 400 ms
5%
Adjustable: 0.5 10 s
1.5 s
1x SPDT
250 V AC1, 24 V DC
8 A AC1
2500 VA AC1, 240 W DC
3.75 kV
3 x107 switches
0,7x105 switches
24 V 240 V AC / DC
nominal voltage
15% ... +10%
max 2.5 VA / W
-20 C ... +55 C
max. 2.5 mm2 / with insulation 1.5 mm2
Class II.
IP 20
DIN EN 60715 rail
72 g

Voltage range allowed

Power consumption
Ambient temperature
Electrical connection
Electrical protection
Ingress protection
Mechanical connection
Mass

KSK- KSP201 201

Type
Nr. of probes
Insulation of
socket
Cable
gland
Process
connection

KSS201

KSN201

1
ABS

PP

KSH203

KSH204

KSH301

KSH302

2+r

3+r

4+r

1+r

2+r

PFA

PP

Housing material
Medium
max 80C
temperature
Max. pressure

0.3MPa
Ingress protection

Mass
0.05 kg

KSH304

3+r

4+r

M20x1.5
cable diameter 6 ... 12 mm

3/8 BSP

KSH303

M4 nut,
rubber cap protected

Pg 9

Socket material

KSH202

1 BSP

A44
c. steel

KO35
stainless steel (1.4571)
Paint coated aluminium cast

KLN2

KLP201

KLP204

M6

KO35
1.4571

PP
PBT

max 200 C

max 80C

1.6 MPa

0.3 MPa

0.22 kg/m

IP 20
0.1 kg

IP 65
0.4 kg

PP
max
80C

PVDF
max
130C

r =reference probe

2.2 ORDER CODES

NIVOCONT

KRK 512

Power supply
24-240 V AC/DC

NIVOCONT KS

CODE
5

TYPE
Cable probe
SINGLE PROBE
PP socket
Carbon steel socket
St. steel socket
MULTIPLE PROBES
St. steel socket

NIVOCONT KLN 2

Probe length*
0.5 m 3 m

CODE
05 30

CODE
K

HOUSING MAT.
Aluminium
Plastic

0
CODE
2
3

CODE
1
2
3
4

PROBE NUMBER
1 + ref. probe*
2 + ref. probe
3 + ref. probe
4 + ref. probe

P
S
N

* only plastic version

Separator:
NIVOCONT KLP 201
NIVOCONT KLP 204

* to be ordered in 0.5 m units

for plastic version

for aluminium version

2.4 DIMENSIONS
17,6

64
35

14

~ 114

16

M20x1.5

35

90
67,5
45

Lt.55

3/8" BSP
42

~ 147

85

S=22

M6 nut

M6 nut
1 BSP
3,4

SWITCHING UNIT

CABLE PROBE

PROBE SOCKET

PROBE SOCKET

PROBE

KRK-512-5

KSK-201

KSH-20

KSP-201 / KSS-201 / KSN-201

KLN-2

89

M20x1,5

38

121

22

Uninsulated reference probe

1 BSP

80

33

22

38

M6

PROBE SOCKET
KSH-202

KSH-203

SEPARATOR
KSH-204

KLP-204

PROBE SOCKET

SEPARATOR

KSH-30

KLP-201

3. INSTALLATION

5.4. LEVEL CONTROL

KRK-512-5 switching unit can be mounted on DIN EN 60715 rail.

It is recommended that the KLN-2 type probes are cut to the length required for level
detection on site. The probes should be screwed into the KS-20 type sockets.

NIVOCONT KRK-512-5 can be

used for control of filling or
emptying.
During filling control the PUMP
switch should be in position UP
and during emptying control in
position DOWN. That way in
case a power supply outage
occurs
(energised
relay)
overfilling or unwanted emptying
is prevented.

ALWAYS REMEMBER TO TIGHTEN THE PROBE WITH AN M6 NUT!

When using KSH-204 type probe sockets the reference probes should be tightened with
special SW hexagonal M6 nuts!
It is suggested that KLP- type separators be used at every 0.5m 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
without running the risk of a short circuit. When a measurement is needed in a well or in a
plastic pipe 2 of them have to be used.

4. ELECTRICAL CONNECTION
If the wall of the tank is
conductive no reference probe
is needed. In this case terminal
C is to be connected to the
tank. On multiple probe units
E1 and E2 are marked with
14, the reference probe is
marked with C. Admissible
length of cable between signal
processor and probes depends
on cable capacity and
conductivity.

Un
E2

E1

A1

A2

E1

E2

16

15

18

max

min

FILLING
Un

Un
A1

A2

E1

E2

max

A1, A2 - power supply

C - reference probe
E1 - upper level probe
E2 - bottom level probe
15, 16, 18 - relay output

min

16

15

18

max
level
min

t1

EMPTYNG
Un

max
level
min

t1

Connections for NIVOCONT KRK-512-5

5. PUTTING INTO OPERATION

5.1. ADJUSTMENT

6. MAINTENANCE, REPAIR

The green LED (Un) shows that the unit is on, and the energised state of the relay is
indicated by the red LED. Operating mode and delay time (ON and OFF) can be set with
the rotary selector switch and potentiometer on the front panel.
To set the sensitivity using SENS potentiometer do the following: submerge all probes into
the fluid. Set a minimal delay time (t). Adjust the sensitivity from min. to max. value until the
relay becomes energised. Now set the sensitivity a little higher, but dont set a higher
sensitivity than needed.

krk5121a0600h_02
July 2008.
Nivelco reserves the right to change technical data without notice!

max

Function
3
t 2
[s ]
1

4 5 6 7

8
9
10

Probe connection terminal

15

18

Output terminals

Front panel of NIVOCONT KRK-512-5

5.2. LED INDICATION

Green LED is on
Red LED is on
Red LED is off
Red LED blinking

power supply is on
relay is switched on (contacts 15 and 18 are closed)
relay is disconnected (contacts 15 and 16 are closed)
output delay indication

5.3. SINGLE-LEVEL MONITORING LIMIT SWITCHING

If KRK-512-5 is monitoring only one
level, the sensor probe should be
connected to both E1 and E2
terminals. For High Fail-safe mode
indication the PUMP switch should be
in UP position and for Low level alarm
indication in DOWN position. Level
alarm conditions are indicated in the
same way (by de-energised relay
state) as when a power cut-off occurs.

8. WARRANTY

Output indicator (red LED)

Probe sensitivity adjustment

16

Relative humidity: max. 85%

E2
Un

Delay adjustment

Ambient temperature: -30 70 C

Probe connection terminals

A2

E1

Power supply indicator

(green) LED

7. STORAGE

All Nivelco products are warranted free of defects in materials or workmanship for a period
of two years from the date of purchase, as indicated in the Certificate of Warranty.

Power supply terminals

A1

The device does not require regular maintenance.

Repair within and beyond the warranty period is carried out at the Manufacturers location.

Un
A1

A2

E1

E2

16

15

18

max