> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt

# 4-20HR-MaxSonar-WRMI(MB7489)

**Type:** Product page · **SKU:** SEN0266 · **Brand:** [DFRobot](https://core-electronics.com.au/brands/dfrobot-australia)
**Page:** https://core-electronics.com.au/4-20hr-maxsonar-wrmi-mb7489.html ([markdown](https://core-electronics.com.au/4-20hr-maxsonar-wrmi-mb7489.html.md))

The MB7489 4-20HR-MaxSonar-WRMI sensor of weather resistance has millimeter resolution and a 7.5Hz read rate, provides short to long distance detection and range...

## Pricing

- **Price:** $219.95 (inc GST) — $199.95 AUD, exc GST
- **Quantity discounts:** 6+ $189.95 (exc GST) · 12+ $181.95 (exc GST)

## Availability & dispatch

- Out of stock — the product page offers email notification when it returns.

## How to buy

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- **Checkout** is completed on-site and includes a captcha at the payment step. Share the cart link; checkout takes it from there.
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- **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt
## Description

The MB7489 4-20HR-MaxSonar-WRMI sensor of weather resistance has millimeter resolution and a 7.5Hz read rate, provides short to long distance detection and range information from 500mm to 5000mm to the target with the largest acoustic return and features the industry standard 20-4mA output where 20mA is minimum range and 4mA is maximum range.
The MB7489 from the 4-20HR-MaxSonar-WR line of outdoor sensors is a rugged ultrasonic sensor component module. This sensor comes in a compact and robust PVC housing which meets the IP67 water intrusion standard and matches standard electrical 3/4-inch PVC pipe fittings (this product has multiple housing options available).
The 4-20HR-MaxSonar-WR sensors are factory calibrated to match narrow sensor beam patterns and provide reliable long-range detection zones.
The MB7489 is designed to report the distance to the largest acoustic return while ignoring smaller targets. When targets are of similar amplitude reflections, preference is given to the closest target. This gives users the flexibility to consistently detect larger targets in the presence of clutter and noise.
If the largest target is removed from the field of view, the MB7489 will switch to the target that gives the next largest detectable return. This filtering makes the MB7489 one of our most advanced sensors for outdoor tank and bin applications.
In addition, the MB7489 offers virtually noise free distance readings through the use of high-output acoustic power combined with continuously variable gain, real time background automatic calibration, real time waveform signature analysis, and noise rejection algorithms. This holds true even in the presence of many of the various acoustic or electrical noise sources.

 ![4-20HR-MaxSonar-WRMI(MB7489) Beam Pattern](https://core-electronics.com.au/attachments/localcontent/BeamPattern_1585013e533.png)### Specification

- Resolution of ~1.6mm
- 42kHz ultrasonic sensor
- Model: MB7489
- Operating Voltage: 10V~32V
- Operating Current: 40mA
- Range Information: 50cm~500cm/19.69”~196.85”(objects closer than 50cm typically range as 50cm)
- 7.5Hz read rate
- Analog current output of 4-20mA
- Operating Temperature: -40°C to +65°C (-40°F to +149°F)
 
### Documents

- [4-20HR-MaxSonar-WRMI Datasheet](https://core-electronics.com.au/attachments/localcontent/4-20HR-MaxSonar-WR_Datasheet_126108c85bc.pdf)
 
### Parts List

- 4-20HR-MaxSonar-WRMI(MB7489) x1

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/s/e/sen0266-900x600.jpg)