Monitoring

Different Philosophy of Water Detection - Water Leak Detection Sensor Cable

There are 2 ways of water detection that we use in HW group for remote site monitoring:

1) SPOT Water Detection;

2) WLD (Water Leak Detection) with the sensing cable.

The SPOT water detection is much, much cheaper from a sensor point of view, but the physical environment should be adjusted to deliver water in minimum volume to the water detection sensor. The physical environment adjustment is typically much more expensive than the sensor itself. 

The WLD (Water Leak Detection) with sensing cable uses the sensing cable placed at locations where you first expect the water. Water (liquid) is detected along the entire length of the WLD sensing cable. It's more expensive from the sensor’s price perspective, but you can detect really few drops of water in real installations. 

Yes, we are talking about a 20x higher price from the installation cost point of view, but time is critical in these applications. Are you paying for early water detection (within 15 minutes) or swimming invitation (within 15 hours)?

Experience from real installations

There are several water detection sensing cables on the market. The problem is to choose a system that is suitable not for long pipelines, but for real buildings:

a) Sensing cables with a bend limit must be installed under all other cables in the building and well fastened to the ground. It's hard to guarantee this with an external installation company. 
b) Finding a water spot based on distance of detection on the sensor cable is a great feature for the pipes, but not for the buildings. There is zone system much easier to understand in the real installation. 
c) Some sensing cables use capacitive detection and use non-insulated wires as part of the sensing cables. It's a significant limitation factor for installations on the metal floors.
d) Sometimes you need to extend the water sensing cable with non-sensing cable. And you need to realize when on site, not based on the prepared project. Easy to cut/extend non-sensing cable offers great help in these scenarios.

HWg WLD sensing cable

HW group's WLD (Water Leak Detection) Type A sensing cable is a three-state sensor designed to detect any conductive liquid along its surface. 

The maximum length of a WLD zone is 185 meters of sensing cable. The liquid is detected along the entire length of the WLD sensing cable. This means that the entire zone (area) is monitored at one time as an entire area. We can't say at which exact point (distance) of the cable the water was detected, but we are able to detect water quickly and reliably.

It is recommended that multiple WLD zones be used to detect water stains, even within the same room.

Each WLD zone reports 3 states to the monitoring unit:

- 0 = Not flooded
- 1 = Flooded
- 2 = Disconnected

This means that you will also know if something happens to the cable that maintains the monitored zone. Since our sensing cable is robust and can be installed in a variety of ways due to its characteristics, we want to be sure that the operator knows not only if water is detected, but also if something happens to the cable itself.

The WLD sensing cable from HW group has several unique features

• No Bend Limit

Unlike many water detection cables, the WLD sensing cable doesn't have a bend radius limit. It can be knotted and still work, which means installation is easy and doesn't require special training. HW group's WLD sensing cable can be installed with the other cables in the cabling system. This can save you a lot of money during installation. 
No bend limit for the WLD sensing cable also means no cable movement would cause false alarms.

• No Grip Limit

Point pressure within a reasonable range won't change the functionality of the cable. You can step or press on the cable without triggering an alarm. It could be routed even over the door sill.

• No Twist Limit

Like any other electrical cable, the WLD sensing cable can be twisted. No twist limit for the WLD sensing cable also means that no cable movement after installation would cause a false alarm.

• No Reuse Limit

After the liquid is detected and hopefully stopped from flooding the monitored facility, the cable simply dries out and resumes its primary function.

WLD Project Design

The WLD sensing cable makes it possible to implement a surface water detection monitoring system, not just spot detection. One or two spot detectors are not enough to monitor a large area, while with the sensing cable and various WLD devices you can create as many zones as you want - real world scenarios in larger facilities could have up to 50 separate zones with the cable installed around the entire perimeter of a room or any other given space.

Yes, the WLD sensing cable is more expensive compared to spot-detector based leak monitoring, but it's also much faster and more reliable in delivering the alarm when the water is present - it's a 15-minute reaction alarm instead of hours of waiting for the two contacts on the detector to be properly flooded along with everything else on the floor.

With the simple and quick installation and long-term reliability of the WLD system and its components, the combination of sensing cable with non-sensing cable segments ultimately makes it a cost-effective solution for those organizations where early detection of just a few drops of liquid could mean saving the entire business.

Summary

The WLD (Water Leak Detection) system is based on the WLD sensing cable type A for detection. The whole WLD system consists of different products (with WLD zone inputs) aimed at different usage scenarios - from smaller installations to the really huge ones. Sites with LAN / WiFi or with LTE / NB-IoT connectivity. But as the heart of any WLD system, the WLD sensing cable connected to the WLD zone connector is its most critical part.

At HW group, we are focused on providing long-term reliable service to our customers. If you use our monitoring device for a temperature alarm, it must work now and in 2 / 5 / 8 years without touching it. Through our support requests, we see that a significant percentage of our customers repeat the same mistake again, and we would like to offer a solution.

HW group has several intentions when designing remote monitoring solutions:

1. All our products must be installed by experienced IT professionals within 1 hour;
2. We do our best to provide long-term stable service without false alarms;
3. We maintain compatibility in the terminology of our hardware, interfaces and concepts.

Many customers ask for very basic functionality: an email alert when there is a temperature problem at the remote site. Yes, it can be upgraded to SMS alerts, repeated, escalated, but it's all beyond the basic functionality of simple email alerts.

Since the beginning of the Internet, SMTP (Simple Mail Transfer Protocol) was the easy-to-use service for this kind of purpose. We all learned in the 90's to simply send the email alert from the device to the SMTP server and that was it.

If you are inside corporate network, sending alert emails via SMTP server is still a valid idea. You know your SMTP server, someone is responsible for its maintenance.

But if you are using for sending alert emails through the public SMTP server like those listed below, you should change your mindset. Since the 90's there is one big game changer: SPAM.

Public SMTP servers we have tested:

• Gmail.com
• Office365.com
• Outlook.com
• Hotmail.com
• smtp-mail.outlook.com
• GMX.com
• GMX.de
• Yahoo.com
• Seznam.cz
• Centrum.cz

These SMTP servers work most of the time for sending alert emails, but it is not a long-term reliable solution. Which is why we offer you more reliable option free of charge.

The 90s are over, let's update our approach to long-term reliable alerting

In the ever-evolving landscape of technology, the passage of time often casts a revealing light on the methods and tools we once relied upon. Twenty or so years ago, the concept of sending alerts via a public SMTP server represented a reliable communications frontier. Today, in 2023, it stands as a testament to the transformation of real-time communications and the emergence of superior alternatives.

Nineties were fine and fun, but long gone

Using public SMTP servers is unreliable in the long run

The rapid expansion of networks has increased the amount of data flowing around the world, changing our habits, our experiences, our lives. Not surprisingly, the protocols at the heart of the technologies we use every day have evolved as well.

In the late 90s and early 00s, sending an alert email through a public SMTP server (such as gmail.com or GMX.com) was one of the few ways to send email from a remote device. Today, email alerting would probably be just one of many alerting options, but it's still very popular in the IT community. However, the fact that the embedded device sends email through the public SMTP server does not guarantee that it will be delivered to your mailbox. The fact that you tested it by pressing the "send test email" button on the remote monitoring device's website and it worked today does not guarantee that it will be delivered tomorrow, or in one or three years! And we are talking about early email alert that protects temperature conditions on your remote site, environment in the technology room of the company or institution of your paying customer.

To be clear, we are only talking about public (free) SMTP servers. It's reasonable to use your own private SMTP server within your company. You know about server updates, you can use whitelists and so on. This is not the case with public mail servers.

Why it's not a good idea to use free SMTP servers for alerting?

Free SMTP servers are dedicated for standalone client, smartphone client and for daily use of this service. It's not dedicated for embedded thermometer to have an active user account for 5 years without sending an email and then bulking 10 emails within an hour. Of course, the SPAM protection in these services will identify your email alerts as spam activity and will ignore your emails.

Why is it a bad idea to use public SMTP servers in 2023?

• SPAM issues: Public SMTP servers are constantly improving their protection against SPAM messages. Your personal computer, laptop or smartphone doesn't have a problem with this, but a 3-15 year old thermometer is another story.
• Deliverability issues: Due to strict email authentication requirements (such as SPF, DKIM, and DMARC), misconfigured email servers can cause emails to be marked as spam or rejected altogether. This can prevent legitimate email from reaching its intended recipients.
• Blacklisting: Email servers and IP addresses can end up on email blacklists for a variety of reasons, such as sending too much spam or experiencing security breaches. Being blacklisted can result in email delivery failures.
• Server downtime: Email servers can go down for maintenance, hardware failures, or cyber attacks. During these times, email delivery can be delayed or interrupted.
• Limited encryption: Although SMTP supports encryption (SMTPS and STARTTLS), not all email servers and clients implement it properly. This leaves email content vulnerable to interception in transit.
• Full inbox: Have you ever run out of space on the public email service? Haven't yet?
• Overreliance on email: In an era of instant messaging, collaboration tools, and remote monitoring centers, organizations and individuals may rely less on email for critical communications, reducing the urgency to address its reliability issues.

Email popular and easy to use alerting option. But the long-term reliability of free SMTP servers is not the same today as it was in the past. The truth is that public SMTP servers and services have gone through a huge, transitional change over the past two decades. And encryption has been a big part of that change, as we're now moving into a world of mostly encrypted communications.

Take a look at this timeline:

• SSL 1.0 (1994): The first version of SSL was never released to the public due to security vulnerabilities.
• SSL 2.0 (1995): The first public release of SSL, but it had significant security flaws. It introduced the concept of a secure handshake and encryption of data in transit.
• SSL 3.0 (1996): SSL 3.0 addressed the vulnerabilities in SSL 2.0 and became widely used to secure Web communications.
• TLS 1.0 (1999): Transport Layer Security (TLS) was introduced as an upgrade to SSL 3.0 to address vulnerabilities and improve security. TLS 1.0 maintained compatibility with SSL 3.0.
• TLS 1.1 (2006): TLS 1.1 included security enhancements such as protection against Cipher Block Chaining (CBC) attacks and more secure hash functions.
• TLS 1.2 (2008): TLS 1.2 further enhanced security by introducing support for advanced encryption algorithms, including AES-GCM and SHA-256.
• TLS 1.3 (2018): TLS 1.3 is the latest and greatest standard for securing Internet communications. It brings significant improvements in security, performance, and reduced latency. Notable features include faster handshakes, elimination of insecure cryptographic algorithms, and perfect forward secrecy.

With any of these developments in encryption technology, you would probably need to make sure that the alerting device is still connected to the public SMTP service provider. And we're not talking about captchas and other human verification methods that add another layer of complication. 

Another major change was the introduction of a separate username and password for the SMTP client that is different from the end-user username and password. This further complicates the device's integration with the public SMTP server, making it more difficult for an ordinary user to get the system to work reliably in such a configuration. And having to check a hidden box somewhere to continue using an embedded system is not the answer.

Easy to use & long-term reliable solution?

Long-term reliable email alerting is a critical part for 20-50% of HW Group customers. To provide you with "only" our own SMTP server will be very limited solution.

We have a better solution for you with device invalid (disconnected) alerts, graphs and one place to manage all alerts: Portal. In free version for up to 20 devices connected to one user account: www.HWg-cloud.com.

Providing a long-term reliable solution is exactly why HW group develops the SensDesk technology portal. To give HWg customers a long lasting approach to send a mission critical alert and assure the user that the message has been sent.

Of course, it means that you have to learn the portal features, accept that it will take you another 15 minutes, +15 minutes to learn how to set it up and work with it.

Email alerts from the portal (considering the free HWg-cloud.com):

1) User is notified when the sensor goes above or below the user-defined safe range.
2) User will be notified in one hour if the monitoring device is disconnected (Internet or power outage).
3) All emails are managed in one place. It's easier to update email addresses when someone leaves the company and email needs to be updated.

Is this really free?

Yes, email alerting, device invalid alert and 10 days history with graph are free at www.HWg-cloud.com. HWg provide this as a service for their devices.

Only for longer history, SMS alerts, PDF reports and other services you will need to pay for the portal, either www.SensDesk.com or solutions from local portal providers.

What is RME (Remote Monitoring Ecosystem)?

In HWg we provide much more than just the email alerting monitoring device. Even with the cheapest STE2 LITE device you can use the whole ecosystem of our RME services:

• SMS-Gateway for SMS and voice call alerts
• UPS for power backup
• HWg-cloud for free or paid SensDesk subscription
• XML and SNMP API
• HWg Monitor application

Summary

Do not rely too heavily on the public SMTP server, especially for mission-critical alerts. The 90s are over. Yes, you can save 30 minutes and rely on a free SMTP mail service. 

But every single SPAM protection measure implemented by this free service will probably disable your email alerts and you won't get any notification about it.

Use HW Group's portal service. It's free and much more reliable in the long run. The HWg-cloud.com or the paid SensDesk.com portals. Both would save your time and effort and eliminate the loss if the alert isn't delivered on time.

4 simple reasons to use HWg-cloud free Portal:

WiFi & LAN monitoring for any application

HWg STE2 is a series of measuring and monitoring devices designed to connect digital sensors for various parameters (temperature, humidity, air quality/CO2, water leakage, electrical voltage or current, etc.) on one side and to connect to a local computer, laptop, tablet or smartphone via standard wired LAN Ethernet or wireless WiFi communication on the other side, using an Internet connection (LAN or WiFi router).

In hotels and lodging, pharmacies and healthcare, various stores and retail chains, warehouses and storage facilities, the monitoring devices collectively referred to as STE2 can be used flexibly and effectively. Since different environments and applications require different numbers of sensors, monitoring, evaluation and communication services, three different versions are available with appropriately graded features and corresponding prices:

• STE2 PLUS - professional monitoring of various parameters, even for large systems, using 1-Wire and digital sensors.
• STE2 R2 - flexible monitoring of temperature and humidity in different environments using 1-Wire and digital sensors.
• STE2 LITE - easy monitoring of temperature or air quality.

All STE2 units have several features in common

They can measure the following parameters:

• Measurement of outdoor and indoor temperatures in the range -200 to +200 °C.
• Measurement of relative humidity from 5 to 95% RH.
• Measurement of air quality/CO2/VOC.
• Water presence/leakage detection.
• Measurement of DC and AC electrical voltage (up to 230 V) and DC and AC power supply current.
• Detection/measurement of light presence and intensity.

1) All STE2 devices provide both LAN and WiFi remote connections to a computer or LAN/WAN router.

2) They can also be connected to a smartphone application, HWg Monitor (Android or iOS).

3) Optionally, they can be connected to the Internet cloud portal HWg-cloud.com (free for small basic applications).

STE2 PLUS - Professional Environmental Monitoring

STE2 PLUS is the latest addition and a professional product for remote monitoring of systems and environments via external sensors and LAN or WiFi networks. It supports fixed IP addresses as well as DHCP and provides higher security through HTTPS certificates, TLS authentication, SNMPv3 and IPv6. Whenever the measured values of parameters exceed or fall below predefined limits, an alert is sent. In this regard, STE2 PLUS directly supports sending SNMP traps and e-mail alerts (via SMTP) or disconnecting the device via the HWg-cloud.com portal service. The device can be connected to the network via WiFi IEEE 802.11 b/g/n or LAN 10/100Mbit (built-in RJ45 port) and can also use XML API for integration with third-party systems.

Sensors can be connected to two RJ11 ports. In addition, sensors can be daisy-chained to provide a total of up to 15 readings from different types of 1-wire sensors. A physical sensor can provide not only a specific measurement (e.g. %RH, cryo temperature, CO2, VOC, 4-20mA, flood detection, etc.), but in some cases multiple measurements simultaneously (e.g. °C + %RH + VOC = 3 measurements). In addition, digital/two-state sensors with switchable outputs can be connected to two digital inputs for detectors. Using relay outputs on another LAN device connected to the same cloud portal, the STE2 PLUS can control up to 8 supported VDO (Virtual Digital Output) devices.

The STE2 PLUS package includes a 5V power supply and a 3m temperature sensor cable with RJ11 connector. The unit can also be powered using Power over Ethernet (PoE) technology.

Typical Use Case - data center and server room monitoring

Do you have large data centers, server rooms or control centers with a significant amount of IT and computer equipment? As is well known in this industry, it is critical to monitor the environment, whether it is a room or a specific rack. Data centers typically represent hundreds of thousands or millions of dollars of investment. Therefore, when certain events occur, the consequences can be even more significant due to the data stored and managed. Possible consequences include component overheating leading to a fire hazard, room flooding including distribution racks, or unauthorized access and data loss or tampering. The STE2 PLUS can monitor, track and alert on temperature, humidity and potential flooding or proper power supply anywhere in cabinets or racks by daisy-chaining up to 15 1-wire sensors up to 60 meters apart. Industrial use in distribution racks is also supported, including DIN-rail mounting with an additional bracket.

Other potential applications include:

• Control systems, control rooms, IT centers, racks -> monitor temperature, humidity or flooding in multiple locations simultaneously.
• Medical facilities - refrigerators, freezers, drug storage -> monitor stable temperature and humidity conditions.
• Large food warehouses/supermarkets -> control stable storage climate in multiple locations (temperature, humidity, air pressure), create HACCP protocols using application software.
• Large greenhouses & nurseries -> efficient monitoring of temperature, humidity and possibly lighting simultaneously in different locations.
• Archives, libraries, museums -> environmental control of exhibits and air quality for visitors.
• Large public buildings -> monitoring of CO2, temperature, humidity + security options (PIR, smoke detection, flooding).
• Heat exchange stations and building distribution systems -> monitoring for water leaks or flooding.

STE2 R2 - Reliable Remote Temperature and Environmental Monitoring

STE2 R2 is primarily designed for remote temperature measurement and other parameter monitoring in less extensive applications and services compared to STE2 PLUS. However, many functions are shared. Again, two RJ11 ports can measure up to 5 different values from 1-Wire sensors, and two DI (digital inputs) can monitor the on/off status of various external devices equipped with switchable relay outputs or various detectors (e.g. smoke or door contacts). The device supports a web interface, Open API (SNMP, XML), sending alerts via email (SMTP) or SMS (through an external SMS-GW-LTE unit).

Another feature is the ability to connect STE2 R2 to the cloud (Internet) portal HWg-cloud.com, which allows easy monitoring and management of the device via a web browser on any PC, tablet or smartphone. The portal centralizes device management, graphs and provides email alerts. You can define up to 3 sets of targets and assign them to individual sensors. PDF reports are also available. SMS alerts can be sent using an SMS-GW3 gateway with a SIM card.

However, the use of the Cloud Portal is optional, as STE2 units can operate without it (i.e. without connecting the device to the Internet). For complete configuration, it has a built-in web server that allows the use of any local PC with a web browser over a local wired Ethernet or wireless WiFi network. You can also download HWg-PDMS PC software for graphing and data export to MS Excel without connecting STE2 R2 to the Internet or Cloud Portal (free for use with a maximum of 3 sensors).

Each STE2 R2 package includes a power supply and an external temperature sensor (3 meters long). Additional sensors and accessories can be purchased as needed.

Typical use case - monitoring constant temperature and humidity in refrigerators

Pharmacies and medical companies are required to comply with standards and regulations. To ensure compliance, they must monitor the temperature in refrigerators and storage rooms where medicines and temperature-sensitive items are stored. However, hiring employees to monitor individual refrigerators and storage rooms is expensive and less reliable. This problem requires an appropriate and reliable monitoring service. The STE2 R2 measuring devices and the monitoring portal HWg-cloud.com offer a solution. This combination helps to set and monitor safe temperature, humidity and motion detection values for safe storage of medicines. It allows you to receive alerts when a problem occurs and provides reports on monitored values to confirm regulatory compliance.

Other potential applications include:

• HVAC monitoring - remote monitoring of air conditioning functionality -> temperature, humidity or separate water tank monitoring.
• Shops/Restaurants - remote monitoring of refrigerators or freezers -> power supply control and temperature stability.
• Heating Optimization -> short and long term temperature, humidity and dew point graphs in different building locations.
• Offices, schools, public spaces, government offices -> environmental quality and air quality control (temperature, humidity, CO2, VOC).
• Industrial switchboards -> long-term monitoring of AC and DC voltage and current + environmental monitoring (overheating, undercooling, humidity).

STE2 Lite - Simple Environmental Monitoring

STE2 Lite is a simple LAN and WiFi thermometer, hygrometer, and air quality monitor for remote monitoring of businesses, homes, or cottages. It can also be very useful for checking environmental conditions in unoccupied homes or small warehouses. Do you need the ability to check the temperature, humidity or air quality in your basement, warehouse, garage, cottage or any room at any time? It's easy with STE2 LITE. You can also set monitoring levels, and when the temperature exceeds the specified range, an alert is sent via email to your smartphone. Using the external SMS-GW-LTE gateway, you can send alerts via SMS, make calls to older phones, or even establish a wireless connection to the HWg-cloud.com portal service (free for some initial applications and basic features).

Although STE2 Lite has only one RJ11 connector, it can measure up to 4 values of different parameters depending on the type of connected sensor (in addition to temperature, it can measure e.g. %RH - relative humidity, CO2, VOC, electric voltage up to 230 V). In addition, some sensors provide several measured values simultaneously (e.g. °C + %RH = 2 values).

The basic STE2 Lite package includes a 5V international power supply and a temperature sensor with a 1m cable. Additional sensors can be purchased as needed.

Typical Use Case - Storage Conditions Monitoring

Warehouse operators need an effective and reliable way to monitor temperature and humidity in their storage facilities (refrigerators, freezers, warehouses - archives, cellars, technical rooms) and also in vehicles (both refrigerated and standard). Thanks to the STE2 Lite box, you can ensure that your cargo is stored in the right conditions in your warehouse or during transportation in a vehicle. You can monitor temperature, humidity, water leaks, digital inputs, voltage, current, power consumption and more. You can remotely control the technology via outputs. Configuration is quick and easy, and our sensors can provide data via Ethernet, WiFi, GPRS, or LTE. In the event of overheating, you can remotely control your air conditioning and adjust the temperature to the desired levels to keep storage areas safe and compliant.

Other possible use cases:

• Air conditioner temperature monitoring -> temperature alarm sensor (server temperature monitoring, air conditioner malfunction alarm).
• Monitoring conditions in nurseries and greenhouses -> temperature, humidity, lighting control.
• Simple environmental monitoring in distribution panels -> local distribution panels in offices, family homes and apartment buildings, etc.
• Overheating control of various computers and devices -> local computers in offices or workplaces.
• Offices, schools, public places, government offices -> environmental and air quality control (temperature, humidity, CO2, VOC).

Comparison of STE2 versions Plus / R2 / Lite

Complementary sensors and detectors for STE2

1-Wire sensors:

• Temp-1Wire IP67 (1m, 3m, 10m)
• Temp-1Wire-Flat 3m
• Temp-1Wire Rack 19
• Temp-1Wire-Outdoor 3m
• Temp HomeBox
• Temp-1Wire Pt100 Frost
• Temp-1Wire Pt100
• Humid-1Wire (1m, 3m, 10m)
• HTemp-1Wire 3m
• HTemp-1Wire Rack 19
• HTemp HomeBox
• HTemp-1-Wire Outdoor

1-Wire UNI sensors for additional measurements or input expansion:

• Flood detector 1W-UNI 3m: Spot detection
• Sensor WLD Relay 1W-UNI: Water Leak Detector
• 30A AC Current probe 1W-UNI 2: Sensor for indirect single-phase measurement of AC current up to 30A without cutting the wire
• 30A DC Current probe 1W-UNI
• 100A DC Current probe 1W-UNI
• Sensor 230V AC 1W-UNI
• Sensor 0-20mA 1W-UNI: Isolated DC current sensor for the 1Wire-UNI bus
• Sensor 4-20mA 1W-UNI: Isolated converter for external DC current probes
• Light 1Wire-UNI
• Sensor THPVoc 1W-UNI: Combined sensor of 4 quantities in 4x4 cm indoor box. RJ11 interface (1-Wire UNI bus)
• Sensor CO2 1W-UNI: Combined Temperature, Relative Humidity and CO2 sensor in one box
• Expander 4xDI 1W-UNI

Conclusion

The HWg STE2 series offers a flexible solution for monitoring various environmental parameters in a wide range of applications. Whether you need professional monitoring with extensive sensor support (STE2 PLUS), reliable remote temperature and environmental monitoring (STE2 R2), or simple environmental monitoring for basic temperature, humidity, and air quality checks (STE2 LITE), there's a device to meet your needs. These devices can help you maintain desired environmental conditions, prevent potential problems, and provide peace of mind with remote monitoring and alerting capabilities.

If you’re interested in the STE2 family device, please contact a dedicated distributor in your country.

Links:

• STE2 Plus product page: https://www.hw-group.com/device/ste2-plus
• STE2 R2 product page: https://www.hw-group.com/device/ste2-r2
• STE2 LITE product page: https://www.hw-group.com/device/ste2-lite