
Level control
➜ ENRM
■ Adjusting one or two levels (min./max.)
■ Monitoring filling (UP) or emptying (DOWN) selected
by a switch on the front panel.
■ Probes supplied with AC current.
■ Sensitivity adjustable on front panel from 250 Ω to 1 M
Ω.
■ Time delay preventing wave effect adjustable from 0.1
to 5s.
Specifications
Type Characteristics Voltages Code
ENRM Monitoring filling UP
Monitoring emptying DOWN
General characteristics
Operating range 0.85 ➞1.10 x U n
Maximum power consumption 3 VA
Adjustable sensitivity 250 Ω ➞1 MΩ
Measurement accuracy (at maximum sen sitivity) ± 30 %
Electrode voltage (max) 24 V AC (50/60 Hz)
Electrode current (maximum) 1 mA (50/60 Hz)
Maximum cable capacity 10 nF
Response time high level 300 ms
Response time low level 500 ms
Output relay (according to AC1 resistive load) 1 AgNi changeover relay 8 A AC max.
Galvanic isolation via transformer (4 kV, 8 mm creepage distance) Class II VDE 0551
Isolation of contacts and electrodes from power suppl y 2.5 kV AC
Operating temperature range (°C) -20 ➞+50°C
Storage temperature range (°C) -40 ➞+70°C
Weight (g) 150
24 V AC 84 870 211
48 V AC 84 870 212
120 V AC 84 870 213
230 V AC 84 870 214
Dimensions
ENRM
32
3,5
57
63
95
22,5
A1 15 Y1
78
18 16 A2
5
Products and specifications subject to change without notice.
Order/Technical Support – Tel: (800) 677-5311 / FAX: (800) 677-3865 / www.crouzet-usa.com
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Connections
Adjusting two levels
Monitoring filling "Up"
R
S
T
N
14
A1
S
11
11
12
Min
12 A2
C
14
Max
Monitoring emptying "Down"
R
S
T
N
S
A1
11
11
14
12 A2
C
14 12
Max
2
3
MP
Common
B
Off
C
On
D
Output
E
A1-A2 : power supply
Max.
Min.
2
Max.
1
4
MP
Common
B
Off
C
Output
D
1
3
A1-A2 : power supply
Products and specifications subject to change without notice.
Order/Technical Support – Tel: (800) 677-5311 / FAX: (800) 677-3865 / www.crouzet-usa.com
2

Principles
Operating principle
General principle :
The ENRM monitors the levels of conductive liquids. The principle is based on measuring t he
apparent resistance of the liquid between two submerged probes. When this value is lower than the
preset threshold displayed on the unit’s front panel, the relay changes state. To prevent any
occurrences of electrolysis, an AC current is passed through the probes. A rotary switch on the
front panel can be used to select the desired function and sensitivity range. A level can be
monitored using the 2
In this instance, the max. probe remains above the liquid and an adjustable time delay prevents the
wave effect.
A green LED indicates that the supply voltage is present.
A yellow LED indicates the output relay’s state.
When the green and yellow LEDs are flashing, this indicates an incompatible adjustment position.
Rotary switch in mode 2 - Activation time - Filling function
Monitoring a level, filling function, activation time
(level : 1 - on delay, function Up LS (Low Sensitivity : 250 W to 5 kW) , Up St (Standard Sensitivity:
5 kW to 100 kW) , Up HS (High Sensitivity : 50 kW to 1 MW).
When the level of liquid drops below the probe for a period exceeding the value of time delay T set
on the front panel, the relay energises and remains on until the level of liquid reaches the probe
again.
If the level of liquid returns above the level set before the time delay elapses, th e relay does not
come on.
Note
When the power returns after a power break, the output relay only energises af ter time delay T if
the level of liquid is below the threshold.
B
C
U
1
TT
2
Level
Relay
T
T
nd
rotary switch.
Rotary switch in mode 2 - Activation time - Emptying function
U
Monitoring a level, emptying function, activation time
(level : 1 - on delay, function Dwn LS (Low Sensitivity : 250 W to 5 kW) , Dwn St (Standard
Sensitivity : 5 kW to 100 kW) , Dwn HS (High Sensitivity : 50 kW to 1 MW).
When the level of liquid rises above the probe for a period exceeding the value of time delay T set
1
on the front panel, the relay energises and remains on until the level of liquid drops back below the
probe.
TT
2
T
T
If the level of liquid drops back below the level set before the time delay elapses the relay does not
come on.
Note
When the power returns after a power break, the output relay only energises af ter delay time T if
the level of liquid is above the threshold.
Level
B
Relay
C
Rotary switch in mode 3 - Deactivation time - Filling function
U
Monitoring a level, filling function, deactivation time
(level : 1 - off delay, function Up LS (Low Sensitivity : 250 W to 5 kW) or Up St (Standard
Sensitivity : 5 kW to 100 kW) or Up HS (High Sensitivity : 50 kW to 1 MW).
When the liquid level drops below the probe the relay energises imm ediately and remains on until
1
the level of liquid reaches the probe again and remains above it for a period exceeding time delay T
set on the front panel.
T
2
T
T
T
If the level of liquid drops back below the level set before the time delay elapses, the relay remains
on.
Note
When the power returns after a power break, the output relay energises immediately if the liquid
level is below the threshold.
Level
B
Relay
C
Rotary switch in mode 3 - Deactivation time - Emptying function
Products and specifications subject to change without notice.
Order/Technical Support – Tel: (800) 677-5311 / FAX: (800) 677-3865 / www.crouzet-usa.com
3

U
Monitoring a level, emptying function, deactivation time
(level : 1 - off delay, function Dwn LS (Low Sensitivity : 250 W to 5 kW) or Dwn St (Standard
Sensitivity : 5 kW to 100 kW) or Dwn HS (High Sensitivity : 50 kW to 1 MW).
1
T
2
Level
B
Relay
C
Monitoring two levels, emptyin g functi on
U
1
2
3
Maximum level
B
Minimum level
C
Output relay: Down
D
T
T
T
When the level of liquid rises above the probe the relay energises immediately and remains on until
the level of liquid drops back below the probe for a period exceeding the value of time delay T set
on the front panel.
If the level of liquid returns above the level set before the time delay elapses the relay remains on.
Note
When the power returns after a power break, the output relay energises immediately if the level of
liquid is above the threshold.
Monitoring two levels, emptying function
(level : 2, function Dwn LS (Low Sensitivity : 250 W to 5 kW) , Dwn St (Standard Sensitivity : 5 kW
to 100 kW) , Dwn HS (High Sensitivity : 50 kW to 1 MW).
The output relay remains open as long as the level of liquid has not reached the maximum probe.
Once the maximum level is reached the co ntact clo ses and the tank can then be emptied (valve
opened, pump started, etc). When the level drops bel ow the minimum level the contact opens and
interrupts the emptying process.
Note : when monitoring two levels the time delay preventing the wave effect is not in operation.
Note
When the power returns after a power break, the output relay energises immediately if the level of
liquid is above the threshold.
Monitoring two levels, filling function
U
1
2
3
Maximum level
B
Minimum level
C
Output relay: Up
D
Monitoring two levels, filling function
(level : 2, function Up LS (Low Sensitivity : 250 W to 5 kW) or Up St (Standard Sensitivity : 5 kW to
100 kW) or Up HS (High Sensitivity : 50 kW to 1 MW).
The output relay remains on as long as the level of liq uid has not reached the maximum probe. As
soon as the maximum level is reached the contact opens and pumping stops. When the level drops
below the minimum level the contact closes again an d pumping restarts to bring the level of liquid
back up.
Note : When monitoring the two levels the time delay preventing the wave effect is not in operation.
Note
When the power returns after a power break, the output relay energises immediately if the level of
liquid is below the threshold.
Other informations
The probe cable (maximum length 100 metres ) does not have to be screened, but avoid mounting it in parallel with the power supply cables. A screened
cable can be used with the screening connected to the common terminal.
Products and specifications subject to change without notice.
Order/Technical Support – Tel: (800) 677-5311 / FAX: (800) 677-3865 / www.crouzet-usa.com
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