Datasheet
HNM and HNE control relays are designed to monitor the levels of:
-
Conductive liquid (HNM)
- Any other product (HNE)
The HNM relay takes its measurements by means of resistive probes.
The HNE relay takes its measurements by means of discrete sensors.
Both these products actuate their output relay during emptying or filling of a tank.
HNM relays control levels of conductive liquids. The principle is based on measuring the apparent resistance of the liquid between two submerged probes. When this value is below the preset
threshold displayed on the front face of the unit, the relay changes state. To avoid electrolytic phenomena, an AC current runs across the probes. A rotary switch on the front face can be used to
select the desired function and sensitivity range.
HNE relays control levels of products which may or may not be conductive. High and low-level data is produced by 3-wire output discrete sensors.
A green LED indicates the presence of the supply voltage.
A yellow LED indicates the status of the output relay.
A yellow LED flashes during the time delay.
A rotary switch on the front face can be used to select the sensitivity range, and the emptying or filling function.
A second switch can be used to select the number of levels (1 or 2), as well as the type of time delay in the case of 1-
level mode.
The configuration of these switches is taken into account on energisation.
Certifications
UL, CSA, GL
Conformity with environmental directives
RoHS, WEEE
Supply
Power consumption at Un
5 VA in AC/1.5 W in DC
Immunity from micro power cuts
90 ms max. in AC/ 100 ms max. in DC
Output
Type of output
1 double changeover relay
Timing
Maximum reset time
4 s
Inputs and measuring circuit
Measurement range
250
Ω
→1M
Ω
Low sensitivity adjustment (LS)
250
Ω
→5k
Ω
Standard sensitivity adjustment St
5 k
Ω
→100k
Ω
High sensitivity adjustment (HS)
50 k
Ω
→1M
Ω
Adjustment of sensitivity
5→100%oftheselectedrange
Display precision
±
10% of full scale for LS and St ranges
-40% / +10% of full scale for HS range
Measuring error with temperature drift
0.5% / °C in standardsensitivity
Measuring error with voltage drift
0%/V across the whole range
Max. voltage at probe terminals
5 V / 500 Hz
±
10%
Max. current via probes
< 1 mA
Max. length of probe cables
100 m
Max. capacity of probe cable (nF)
1 nF for HS range2.2 nF for St range4.7 nF for LS range
Input circuit 3
-wire sensors
No
General characteristics
Weight
115 g
Description
Code
Removable sealable cover for 35 mm casing
84800001
Dimension Diagram : HNM
-
HNE
: HNM
-
HNE
Unless otherwise specified, the characteristics given are applicable to all or part of the product range selected
13/03/2012 www.crouzet.com