Features
Level control relays for conductive liquids
72.01 - Adjustable sensitivity
72.11 - Fixed sensitivity
•Emptying or filling functions
•LED indicator
•Reinforced insulation (6 kV - 1.2/50 µs) between:
- supply and contacts
- electrodes and supply
- contacts and electrodes
•35 mm rail (EN 50022) mount
•Control about a single level or between
Min./Max. limits
•72.01 available also for supply 400 V
1 CO (SPDT) 1 CO (SPDT)
16/30 16/30
250/400 250/400
4,000 4,000
750 750
0.55 0.55
16/0.3/0.12 16/0.3/0.12
500 (10/5) 500 (10/5)
AgCdO AgCdO
24 - 110...125 – 230...240 400 24 - 110...125 – 230...240
24 — 24
2.5/1.5 2.5/1.5 2.5/1.5
(0.8...1.1)UN(0.9...1.15)UN(0.8...1.1)UN
(0.8...1.1)UN— (0.8...1.1)UN
100 · 103100 · 103
44
0.2 0.2
0.5 - 7 (selectable) 1
5…150 (adjustable) 150 (fixed)
66
–20…+60 –20…+60
IP20 IP20
72.01 72.11
•Sensitivity range (5...150) kΩadjustable
•Delay time (0.5s or 7s) switch selectable
•Emptying or filling functions switch selectable
•Sensitivity fixed 150 kΩ
•Delay time fixed: 1s
•Emptying or filling functions link selectable
72 Series - Monitoring relays 16 A
Contact specification
Contact configuration
Rated current/Maximum peak current A
Rated voltage/Maximum switching voltage V AC
Rated load AC1 VA
Rated load AC15 (230 V AC) VA
Single phase motor rating (230 V AC) kW
Breaking capacity DC1: 30/110/220 V A
Minimum switching load mW (V/mA)
Standard contact material
Supply specification
Nominal voltage (UN)V AC
V DC
Rated power AC/DC VA (50 Hz)/W
Operating range AC
DC
Technical data
Electrical life at rated load AC1 cycles
Electrode voltage V AC
Electrode current mA
Run-on time s
Max sensitivity range kΩ
Insulation between supply/contacts/electrode (1.2/50 µs)
kV
Ambient temperature °C
Protection category
Approvals (according to type)
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
R = (5…150)kΩ
LEVEL
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
Z1 Z2
T = 1 s
R = 150 kΩ
LEVEL
U = 24 V DC
24 V AC 50/60 Hz
(110...125)V AC 50/60 Hz
(230...240)V AC 50/60 Hz
U = 24 V DC
24 V AC 50/60 Hz
(110...125)V AC 50/60 Hz
(230...240)V AC 50/60 Hz
FL = Filing – 7s delay
FS = Filling – 0.5s delay
ES = Emptying – 0.5s delay
EL = Emptying – 7s delay
F = Filling
E = Emptying
Z1 Z2
Z1 Z2
FS
FS
ES
EL
FL
1
84
35
44.8
54.6
42.3
58
F
OR
UL H
ORSEPOWER AND
P
ILOT
D
UTY RATINGS
S
EE
“General technical information” page
V
3 Phase - Rotation and phase loss monitoring relay
•Universal voltage monitoring
(UNfrom 208 V to 480 V, 50/60 Hz)
•Phase loss monitoring, under phase regeneration
•Positive safety logic - make contact opens
if the relay detects an error
•Small size (17.5 mm wide)
•35 mm rail (EN 50022) mount
•European patent pending for the fully
innovative principle at the root of the 3 phase
monitoring and error survey system
1 CO (SPDT)
6/15
250/400
1,500
250
0.185
3/0.35/0.2
500 (10/5)
AgCdO
208...480
50/60
8/1
170...500
100 · 103
<0.5/<0.5
–20…+50
IP20
72.31
•Phase rotation monitoring
•Phase loss monitoring
72 Series - Monitoring relays 6 A
Contact specification
Contact configuration
Rated current/Maximum peak current A
Rated voltage/Maximum switching voltage
V AC
Rated load AC1 VA
Rated load AC15 (230 V AC) VA
Single phase motor rating (230 V AC) kW
Breaking capacity DC1: 30/110/220 V A
Minimum switching load mW(V/mA)
Standard contact material
Supply specification
Nominal system voltage (UN) V AC 3 ~
Frequency Hz
Rated power VA 50 Hz/ W
Operating range V AC 3 ~
Technical data
Electrical life at rated load AC1 cycles
Switch-off/reaction time s
Ambient temperature °C
Protection category
Approvals (according to type)
L1
A1
3~U
UN= (208...480) V AC 3~
(50/60 Hz)
L2
L3
A2 A3
14 11 12
Features
A1 A2
A3
14
11
12
45
56.5
43.5
26.5
84
17.5
2
72 Series - Monitoring relays 6 -16 A
Level control relays
Example: 72 series level control relay, adjustable sensitivity range, (230…240)V AC supply voltage.
Series
Type
0 = Sensitivity range adjustable (5...150)kΩ
35 mm rail (EN 50022) mount
1 = Sensitivity fixed 150 kΩ
35 mm rail (EN 50022) mount
No. of poles
1 = 1 CO (SPDT)
Supply voltage
024 = 24 V
125 = (110…125)V AC
240 = (230…240)V AC
400 = 400 V AC (72.01 only)
Supply version
8 = AC (50/60 Hz)
9 = DC
0 1 0 08 0 0
Ordering information
... .
24072
Monitoring relays
Example : 3 phase line monitoring relay, phase rotation and loss monitoring, supply voltage (208…480)V AC 3~.
Series
Type
3 = 3 phase AC line monitoring
No. of poles
1 = 1 CO
Supply voltage
400 = (208...480)V AC 3~
Supply version
8 = AC (50/60 Hz)
3 1 0 08 0 0
... .
4 0 072
3
Insulation
Insulation Dielectric strength Impulse (1.2/50 µs)
between supply and contacts 4,000 V AC 6 kV
between electrodes, Z1-Z2 and supply* 4,000 V AC 6 kV
between contacts and electrodes 4,000 V AC 6 kV
between open contacts 1,000 V AC 1.5 kV
EMC specifications
Type of test Reference standard
Electrostatic discharge contact discharge EN 61000-4-2 4 kV
air discharge EN 61000-4-2 8 kV
Radio-frequency electromagnetic field (80 ÷ 1000 MHz) EN 61000-4-3 10 V/m
Fast transients (burst) (5-50 ns, 5 kHz) on Supply terminals EN 61000-4-4 4 kV
Surges (1.2/50 µs) on Supply terminals EN 61000-4-5 4 kV
Radio-frequency common mode (0.15 ÷ 80 MHz) on Supply terminals EN 61000-4-6 10 V
Radiated and conducted emission EN 55022 class B
Other data
Current absorption on Z1 and Z2 mA < 1
Power lost to the environment without contact current W 1.5
with rated current W 3.2
Screw torque Nm 0.8
Max. wire size solid cable stranded cable
mm2 1x6 / 2x4 1x4 / 2x2.5
AWG 1x10 / 2x12 1x12 / 2x14
Max cable length between electrode and relay m 200 (max. capacitance of 100 nF/km)
72 Series - Monitoring relays 6 - 16 A
Technical data for 72.01 and 72.11
4
*There is no electrical isolation between electrodes and supply voltage for the 24 V DC types (72.x1.9.024.0000). Therefore, for SELV
applications it would be necessary to use a SELV (non-grounded) power supply. In the case of a PELV (grounded) power supply take care to
protect the level control relay against harmful circulating currents by ensuring that no electrodes are grounded.
However, there is no such problem for the 24 V AC types (72.x1.8.024.0000) which, by virtue of an internal isolating transformer, assure
reinforced isolation between electrodes and supply.
Insulation
Insulation Dielectric strength Impulse (1.2/50 µs)
between supply and contacts 3,000 V 5 kV
between open contacts 1,000 V 1.5 kV
EMC specifications
Type of test Reference standard
Electrostatic discharge contact discharge EN 61000-4-2 4 kV
air discharge EN 61000-4-2 8 kV
Fast transients (burst) (5-50ns, 5kHz) on A1, A2, A3 EN 61000-4-4 2 kV
Surge (1.2/50 µs) differential mode EN 61000-4-5 4 kV
Other data
Start up time (NO contact closure after energising) s < 2
Regeneration level (Maximum) ≤80% of average of other 2 phase
Power lost to the environment without contact current W 1
with rated current W 1.4
Screw torque Nm 0.8
Max. wire size solid cable stranded cable
mm2 1x6 / 2x4 1x4 / 2x2.5
AWG 1x10 / 2x12 1x12 / 2x14
Technical data for 72.31
72 Series - Monitoring relays 16 A
Functions for 72.01 and 72.11
Contacts
NO output
contact
Supply
voltage
LED
OFF
ON
ON
ON
U= Supply voltage
B1 = Max level
electrode
B2 = Min level
electrode
B3 = Common
= Contact 11-14
Z1-Z2 = Link to select
emptying
(Type 72.11)
Open
Open
Open
(Timing in Progress)
Closed
11 - 14
11 - 14
11 - 14
11 - 12
11 - 12
11 - 12
11 - 12
11 - 14
Open Closed
Function and Run-on time
Type 72.01 Type 72.11
FL = Level control by Filling, Long (7sec) run-on delay. F = Level control by Filling, Z1–Z2 open. Run-on time fixed at 1sec.
FS = Level control by Filling, Short (0.5sec) run-on delay. E = Level control by Emptying, Z1–Z2 linked. Run-on time fixed at 1sec.
ES = Level control by Emptying, Short (0.5sec) run-on delay.
EL = Level control by Emptying, Long (7sec) run-on delay.
Filling functions
Wiring diagram Examples with 3 electrodes
Wiring diagram Examples with 2 electrodes
Type 72.01 Filling Control – between Min.
and Max. levels.
Under normal operation the liquid
level can be expected to cycle
between the Minimum and the
Maximum electrodes, B2 and B1
(plus a degree of over and
under-shoot).
Switch On:
• On “power-up”, if the liquid is
below B1 the output relay will
operate after time T has expired.
• On the liquid level falling below
B2, the output relay will operate
after time T has expired.
Switch Off:
• On the liquid level reaching
electrode B1, the output relay will
de-energise after time T has
expired.
• On “power-off”, the output relay
will immediately de-energise.
Type 72.01 Filling Control – about a single
level, B1.
Under normal operation the liquid
evel can be expected to cycle about
the level set by electrode B1 with a
degree of over and under-shoot.
Switch On:
• On “power-up”, if the liquid is
below B1 the output relay will
operate after time T has expired.
• On the liquid level falling below
B1, the output relay will operate
after time T has expired.
Switch Off:
• On the liquid level reaching
electrode B1, the output relay will
de-energise after time T has expired.
• On “power-off”, the output relay
will immediately de-energise.
U
B1 B2 B3
TTTT
T
U
B1 B2 B3
TT
T
T T
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
R = (5…150)kΩ
LEVEL
Type 72.11
Type 72.11
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
Z1 Z2
T = 1 s
R = 150 kΩ
LEVEL
U = 24 V DC
24 V AC 50/60 Hz
(110...125)V AC 50/60 Hz
(230...240)V AC 50/60 Hz
Z1 Z2
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
R = (5…150)kΩ
LEVEL
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
Z1 Z2
T = 1 s
R = 150 kΩ
LEVEL
U = 24 V DC
24 V AC 50/60 Hz
(110...125)V AC 50/60 Hz
(230...240)V AC 50/60 Hz
Z1 Z2
F = Filling
F = Filling
FS
FS
ES
EL
FL
FS
FS
ES
EL
FL
Level
Level
5
Emptying functions
Wiring diagram Examples with 3 electrodes
Type 72.01 Emptying Control – between Max.
and Min. levels.
Under normal operation the liquid
level can be expected to cycle
between the Maximum and the
Minimum electrodes, B1 and B2 (plus
a degree of over and under-shoot).
Switch On:
• On “power-up”, if the liquid level
is above B2 the output relay will
operate after time T has expired.
• On the liquid level rising to B1, the
output relay will operate after time T
has expired.
Switch Off:
• On the liquid level falling below
electrode B2, the output relay will
de-energise after time T has expired.
• On “power-off”, the output relay
will immediately de-energise.
Type 72.01 Emptying Control about a single level,
B1.
Under normal operation the liquid
level can be expected to cycle about
the level set by electrode B1 with a
degree of over and under-shoot.
Switch On:
• On “power-up”, if the liquid is
above B1 the output relay will
operate after time T has expired.
• On the liquid level rising to B1, the
output relay will operate after time T
has expired.
Switch Off:
• On the liquid level falling below
electrode B1, the output relay will
de-energise after time T has expired.
• On “power-off”, the output relay
will immediately de-energ
U
B1 B2 B3
TTTT
T
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
R = (5…150)kΩ
LEVEL
Type 72.11
Type 72.11
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
Z1 Z2
T = 1 s
R = 150 kΩ
LEVEL
U = 24 V DC
24 V AC 50/60 Hz
(110...125)V AC 50/60 Hz
(230...240)V AC 50/60 Hz
Z1 Z2
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
R = (5…150)kΩ
LEVEL
A1 A2 12 11 14
B1 B2 B3
L/+
N/-
Z1 Z2
T = 1 s
R = 150 kΩ
LEVEL
U = 24 V DC
24 V AC 50/60 Hz
(110...125)V AC 50/60 Hz
(230...240)V AC 50/60 Hz
Z1 Z2
E = Emptying
E = Emptying
EL
FS
ES
EL
FL
EL
FS
ES
EL
FL
Level
Level
72 Series - Monitoring relays 16 A
6
Wiring diagram Examples with 2 electrodes
Applications for 72.01 and 72.11
A1 A2 12 11 14
B1 B2 B3
L3
Max
Com
Min
N
L2
L1
S
A1 A2 12 11 14
B1 B2 B3
L3
Max
Com
Min
N
L2
L1
S
The 72 series level control relays work by
measuring the resistance through the liquid,
between the common (B3) electrode and Min. and
Max. electrodes (B2 and B1). If the tank is metalic,
then this can be substituted as the B3 electrode.
Take care to ensure that the liquid has a
suitable resistivity – see below:
SUITABLE LIQUIDS
- City water
- Well water
- Rainwater
- Sea water
- Liquids with low-percentage alcohol
- Wine
- Milk, Beer, Coffee
- Sewage
- Liquids fertilizer
UN-SUITABLE LIQUIDS
- Demineralised water
- Fuels
- Oil
- Liquids with high-percentage alcohol
- Liquid gas
- Paraffins
- Ethylene glycol
- Paint
FILLING function:
Examples with 3 electrodes and with a
contactor connected to the contact.
EMPTYING function:
Examples with 3 electrodes and with a motor
pump connected directly to the contact.
72 Series - Monitoring relays 6 A
7
Functions for 72.31
L1
UN ≤ 0.8 UN (*)
L2
L3
11 - 14
L1, L2, L3 = Supply voltage
= Contact 11- 14
L1
A1
3~U
UN= (208...480) V AC 3~
(50/60 Hz)
L2
L3
A2 A3
14 11 12
Switch off
- Incorrect phase rotation
- Phase loss
Output contact (11 - 14)
- Closed, if monitored system
healthy
(*) Phase loss monitoring
possible under regeneration
up to 80% of the average of
the other 2 phases
Contacts
NO output
contact
Supply voltage
LED status
OFF
ON
ON
Open
Closed
11 - 14
11 - 12
11 - 12
11 - 14
Open Closed
Supply voltage OFF
- Incorrect phase rotation
- Phase loss
Normal operation
072.01.06
Accessories for 72.01 and 72.11
23
58 6m/15m
072.51
14
9
6
10 119
M4
ch 22
G 3/8”
1 2
8
M4
072.53
80
91
Ø 5
72 Series - Monitoring relays
8
66
2012 23
83
18 10
25
2” GAS
M4
Suspended electrode for conductive liquids, complete with cable. Suitable for level monitoring in wells
and reservoirs not under pressure. All materials used are compatible with food processing applications
(according to European Directive 2002/72 and cod. FDA title 21 part 177).
Order appropriate number of electrodes - additional to the relay.
Cable length: 6 m (1.5 mm2)072.01.06
Cable length: 15 m (1.5 mm2)072.01.15
Technical data
Max. liquid temperature °C +100
Electrode holder with two pole connector, one connected directly to the electrode and the second
connected to the grounded installation thread. Suitable for metal tank with G3/8” linkage.
Electrode not incuded. Order appropriate number of electrodes holders - additional to the relay. 072.51
Technical data
Max liquid temperature °C + 100
Max tank pressure bar 12
Cable grip mm Ø ≤6
Electrode holder with three poles. Electrode not incuded.
Order appropriate number of electrodes holders - additional to the relay. 072.53
Technical data
Max liquid temperature °C + 130
9
072.500
Accessories for 72.01 and 72.11
72 Series - Monitoring relays
072.501
Illustration of interconnection of electrodes.
Electrode and electrode connector, multiple electrodes may be interconneced to provide required length
Technical data
Electrode - 500 mm long, M4 thread, stainless steel 072.500
Inter-electrode connector - M4 thread, stainless steel 072.501
Applications
The main application for these relays is for the sensing and control of the
level of conductive liquids.
Selectable options allow for this control to be achieved either through a
filling operation or through an emptying operation, and in either case
“positive logic” is used.
Level control can be achieved around a single level – using 2 electrodes,
or between Minimum and Maximum levels – using 3 electrodes.
Additionally, the 72.01, with its adjustable sensitivity setting, can be
ideal for monitoring the conductivity of liquids.
Positive safety logic
These relays work according to the principle that it is the closure of a
normally open output contact that will be used to control the pump, both
in filling and emptying applications. Consequently, in the event of a
failure of the supply local to the relay, the filling or emptying will cease.
This is generally considered to be the safest option.
Overrunning of tank on filling
Care must be exercised to ensure that the tank cannot overrun. Factors
that have to be considered are the pump performance, the rate of
discharge from the tank, the position of the single level electrode (or
maximum electrode), and the run-on time delay. Keeping the time delay
to a minimum will minimise the possibility of tank overrun, but will increase
the installed switching rate.
Prevent dry running of pump on emptying
Care must be exercised to ensure that the pump cannot run dry. Similar
considerations must be given as outlined above. In particular, keeping the
run-on time delay to a minimum will minimise the risk, but again, it will
increase the installed switching rate.
Run-on time
In commercial and light industrial applications the use of a short Run-on
time delay is more appropriate, due to the relatively small size of tanks
and the consequential need to react quickly to the change in level.
Larger scale industrial applications involving larger tanks and powerful
pumps must avoid a frequent switching cycle, and the use of the 72.01
set for the longer Run-on time of 7 seconds is suggested.
Note that the short run-on time will always achieve closer control to the
desired level(s), but at the cost of more frequent switching.
Electrical life of the output contact
The electrical life of the output contact will be enhanced where a larger
distance between the Max. and Min. electrodes (3-electrode control)
can be realised. A smaller distance, or level control to a single level
(2-electrode control), will result in more frequent switching and therefore
a shorter electrical life for the contacts. Similarly, the long run-on time will
enhance, and the short time will reduce, electrical life.
Pump control
Small single-phase pumps within the kW (0.55 kW - 230 V AC) rating
stated may be driven directly by the level relay output contact. However,
where very frequent switching is envisaged, it is better to “slave” a higher
power relay or contactor to drive the pump motor. Large pumps (single-
phase and three-phase) will of course require an interposing contactor.
Application notes for 72.01 and 72.11
Electrodes and cable lengths
Normally 2 electrodes or 3 electrodes will be required for control about
a single level, or control between Min. and Max. levels, respectively.
However, if the tank is made of conductive material it is possible to use
this as the common electrode, B3, if electrical connection can be made
to it.
The maximum permitted length of cable between the electrode and the
relays is 200m, for a cable not exceeding 100nF/km.
A maximum of 2 relays and associated electrodes can be employed in
the same tank – if two different levels need monitoring.
Note: It is permitted to make direct electrical connection between
terminals B1-B3, and B2-B3, (without using electrodes/liquid), but in this
case it is not possible to set up the sensitivity.
Electrode choice
The choice of electrodes may depend on the liquid being monitored.
Standard electrodes 072.01.06 and 072.51 are suitable for many
applications but some liquids may be corrosive for example, and may
therefore require custom made electrodes - but these can usually be used
with the 72.01 and 72.11 relays.
On site commissioning
To confirm the suitability of the relay sensitivity to the resistance between
electrodes it is suggested that the following checks are made.
For convenience it is suggested that the fill function and the shortest
run-on time are selected.
Commissioning
Follow these setting-up instructions to achieve correct operation:
72.01
Select the function “FS” (Filling and Short delay of 0.5 s), and set the
sensitivity control to 5 kΩ. Ensure that all electrodes are immersed in the
liquid - expect the output relay to be ON. Then, slowly rotate the
sensitivity control in the 150 kΩdirection until the level relay switches OFF
(internal output relay will switch OFF and red LED will switch
slowly flash).
(If the level relay does not switch OFF then, either the electrodes are not
immersed, or the liquid has too high impedance or the distance between
electrodes is too long).
Finally, select the filling or emptying function as required, run in real time
and confirm that the level relay works as required.
72.11
Select the Filling function “F”, (Z1 – Z2 open). Ensure that all electrodes
are immersed in the liquid, but leave electrode B3 disconnected – output
relay should be ON. Connect electrode B3, and the level relay should
switch OFF
(internal output relay will switch OFF and red LED will switch slowly
flash).
(If the level relay does not switch OFF then, either the electrodes are not
immersed, or the liquid has too high impedance or the distance between
electrodes is too long.)
Finally, select the filling or emptying function as required, run in real time
and confirm that the level relay works as required.
72 Series - Monitoring relays
10
