Crouzet 84870210 Data Sheet

Level control

➜ ENRM

■ Regulation of 1 or 2 levels (minimum / maximum)

■ 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

Part numbers

Type Characteristics Voltages Code

ENRM Monitoring filling (UP)

Monitoring emptying (DOWN)

24

General characteristics

Characteristics

Supply voltage range
Operating range
Maximum power consumption a
Adjustable sensitivity 250 Ω

Measurement accuracy (at maximum sensitivity) ± 30 %
Electrode voltage (max)

Electrode current (maximum) 1 mA
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.
Isolation of contacts and electrodes from power supply

Operating temperature range (°C) -20
Storage temperature range (°C) -40
Weight (g) 91

24

20.4

12 V

2.5 kV

z

➞ 240 V

z

➞ 240 V

➞ 264 V

z

5 VA, c 1.5 W

➞ 1 MΩ

a

a

➞ +50 °C
➞ +70 °C

84 870 210

Dimensions (mm)

ENRM

68

3.5

67.5

45

44

Connections

ENRM

U

+

A1

C Min Max

U

_

23.2

22.5

90

5.5

11

R

12 14A2

2.6

1

Principles

Operating principle

General principle :

The ENRM monitors the levels of conductive liquids. The principle is based on measuring the 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

U

1

TTT T

2

Level

1

Relay

2

nd

rotary switch.

Monitoring a level, filling function, activation time

(level : 1 - on delay, function Up LS (Low Sensitivity : 250 Ω to 5 kΩ ), Up St (Standard
Sensitivity : 5 kΩ to 100 kΩ), Up HS (High Sensitivity : 50 kΩ to 1 MΩ).

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, the relay does not
come on.

Note

When the power returns after a power break, the output relay only energises after time delay T if
the level of liquid is below the threshold.

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 Ω to 5 kΩ ), Dwn St (Standard
Sensitivity : 5 kΩ to 100 kΩ), Dwn HS (High Sensitivity : 50 kΩ to 1 MΩ).

When the level of liquid rises above the probe for a period exceeding the value of time delay T set

1

TTT T

2

on the front panel, the relay energises and remains on until the level of liquid drops back below
the probe.
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 after delay time T if
the level of liquid is above the threshold.

Level

1

Relay

2

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 Ω to 5 kΩ) or Up St (Standard
Sensitivity : 5 kΩ to 100 kΩ) or Up HS (High Sensitivity : 50 kΩ to 1 MΩ).

When the liquid level drops below the probe the relay energises immediately 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 if the liquid level is below
the threshold.

Level

1

Relay

2

2