HNL20-B Integrated Level & Temperature Sensor with LED Display, PNP/NPN

HNL20-B Integrated Level & Temperature Sensor with LED Display, PNP/NPN

Integrated level and temperature sensor with LED display, PNP/NPN switches, 4–20 mA / 0–10 V / RS485 options; 100–1000 mm range (up to 2 m on request), M12 connection, IP67; up to 4 switches and 2 analog outputs.

HNL20-B Integrated Level & Temperature Sensor with LED Display, PNP/NPN

The HNL20-B is an integrated level and temperature sensor with a sturdy LED digital display. It outputs multiple signals at the same time, monitoring level and temperature at several points through one tank opening and reducing the number of enclosure fittings. PNP/NPN switching with freely selectable NO/NC, plus scalable 4…20 mA / 0…20 mA / 0–10 V analog output and an RS485 option, suits equipment upgrade and retrofit projects.

INQUIRY

Displayed Level and Temperature with Multiple Signal Outputs

The HNL20-B suits machine tools and machining centres, hydraulic and lubrication systems, machinery manufacturing, automation equipment, hydraulic power units and oil reservoirs, coolant and lubricant tanks, small oil and water tanks, OEM equipment with limited tank openings, combined level-and-temperature monitoring, industrial retrofit, mobile and compact machinery, and process-control skids. The display and output interfaces can be oriented to site requirements, and the cable routing is adapted accordingly.

Good fit: machine tools and machining centres, hydraulic lubrication systems, machinery manufacturing, automation equipment, hydraulic power units and oil reservoirs, coolant and lubricant tank monitoring, small oil and water tanks, OEM equipment with limited tank openings, combined level and temperature monitoring, industrial equipment retrofit, mobile and compact machinery, process control and skid equipment.

Is HNL20-B Suitable for Your Application?

Choose HNL20-B when:

You need level and temperature monitored together, with on-site display and switch plus analog outputs to a PLC.
The level range fits 100…1000 mm in 50 mm steps (up to 2 m on request), medium temperature within –20…85 °C.
You require PNP/NPN switch points, 4…20 mA / 0…20 mA / 0–10 V analog, or RS485 communication.

Confirm with us first when: the medium is strongly corrosive, pressure exceeds the connection rating, the range exceeds 2 m, or you need an explosion-proof certified instrument.

Integrated Sensor Principle

Displayed, configurable level and temperature

The intelligent menu lets you scale the analog transmission range and adjust switch points continuously. Level provides OUT1/OUT2 PNP/NPN switches with an analog channel; temperature provides OUT3/OUT4 PNP/NPN switches with its own analog channel. Up to four switches and two analog outputs can be configured.

Flexible output architecture

SA: four switches + two analog channels, 8-core aviation plug
S3: three switches, 5-core aviation plug
A2: two analog channels, 4-core aviation plug
RS: RS485 communication, 4-core aviation plug

Analog levels: 4…20 mA / 0…20 mA, 0–10 V / 10–0 V. PNP/NPN and NO/NC are freely switchable; switching current maximum 400 mA.

Built for hydraulic and machine service

DC18…30 V supply, short-circuit and reverse-polarity protection, insulation DC500 V, overvoltage DC36 V, IP67. 304 connecting rod with NBR oil float or 304 water float; POM engineering-plastic housing. 1 million switching-cycle service life.

Technical Specifications

Model	HNL20-B — Integrated level/temperature sensor with display
Power supply	DC18…30 V
Measurement range	100…1000 mm in 50 mm steps; up to 2 m on request
Current consumption	Maximum 600 mA, including switch current
Electrical connection	M12×1 5-pin / 8-pin aviation cable; M12×1 aviation plug per selection
Safety features	Short-circuit protection, reverse polarity protection
Insulation / overvoltage	Insulation DC500 V; overvoltage DC36 V
On-time	<3 s
Switching function	PNP/NPN, NO/NC freely switchable; maximum 400 mA
Response time	Switch output / analog signal 0.2…5 s
Analog load	4…20 mA analog signal ≤500 Ω
Service life	1 million switching cycles
Measurement accuracy	10 mm / 5 mm
Resolution	10 mm default; 5 mm option
Medium temperature	Adjustable; factory default –20…80 °C, up to –20…85 °C
Ambient / storage temperature	Ambient –20…80 °C; storage –20…65 °C
Relative humidity	45…75%
Vibration / shock	20 g, 10…2000 Hz (IEC 60068-2-6); 50 g, 6 ms (IEC 60068-2-27)
Protection rating	IP67
Wetted parts / housing	304 connecting rod, NBR or 304 stainless-steel float; POM engineering-plastic housing

Output Channels

Measurement	Switch outputs	Analog output
Level	OUT1, OUT2 — PNP/NPN	4…20 mA / 0…20 mA; 0–10 V / 10–0 V
Temperature	OUT3, OUT4 — PNP/NPN	4…20 mA / 0…20 mA; 0–10 V / 10–0 V

Selection Code

Code segment	Code	Description
Measurement range	0100…1000	100 mm steps: 0100=100 mm, 0150=150 mm, … 1000=1000 mm
Float type	N	NBR float (oil)
Float type	S	304 float (water)
Resolution	–	10 mm (default)
Resolution	5	5 mm
Output signal	SA	Four switches + two analog channels (8-core aviation plug)
	S3	Three switches (5-core aviation plug)
	A2	Two analog channels (4-core aviation plug)
	RS	RS485 communication (4-core aviation plug)
Electrical connection	M	M12×1 aviation plug

Mechanical Dimensions

Display head with LED screen and side cable glands; 304 rod with NBR or 304 float. Head width 130 mm; float Ø42/Ø40 (304) or Ø32 (NBR), rod length matches the selected range.

Installation and Wiring

Mount through the tank opening so the float slides freely along the rod, clear of the wall, strainer and baffle. Orient the display head and output interfaces to the viewing and cable-routing direction on site. Assign PNP or NPN and NO/NC per the PLC input; configure switch points and analog range in the menu before commissioning. In viscous oil, keep the float path clear of sludge and waxing deposits.

Typical Applications

Machine tools: coolant and lubricant tank level plus temperature monitoring.
Hydraulic systems: power-unit reservoir level, oil temperature and pump protection.
Machinery and automation: OEM level/temperature interlocks and control-panel indication.
Retrofit and skids: equipment upgrade where one opening must carry both level and temperature signals.

What to Send Us for Selection

Send: medium and temperature, required level range, available opening, float preference, required outputs (switch count, analog type, RS485), PNP/NPN and NO/NC logic, and the PLC or instrument input. We will confirm the configuration and selection code before quoting.

Frequently Asked Questions

How many switch points are configurable?

Up to four switches: OUT1/OUT2 for level, OUT3/OUT4 for temperature, each PNP/NPN. The SA version pairs these with two analog channels; S3, A2 and RS cover switch-only, analog-only or RS485 builds.

Can simultaneous analog outputs track continuous level and temperature in one vessel?

Yes. Level and temperature each carry their own analog channel (4…20 mA / 0…20 mA or 0–10 V / 10–0 V), so both continuous signals are available from one instrument through one opening.

How are PNP or NPN outputs assigned for overflow interlocks?

Assign each switch to high or low level in the menu, choose PNP or NPN to match the PLC input, and set NO/NC for the interlock safety logic. Switching current is limited to a maximum 400 mA.

Does viscous oil slow the float response time?

Response time is 0.2…5 s for switch and analog outputs. Heavy viscosity, sludge or waxing can slow float travel; keep the rod clean and verify the float moves freely during commissioning.

What clearance avoids float obstruction near tank walls?

Leave clearance around the rod so the float does not touch the wall, strainer, baffle or heating element, and avoid mounting where settled deposits collect around the float.