We posted a news item on our main site about Trihedral and MultiTrode.

Background

This brief blog post gives a bit of background. Canadian-based Trihedral have been making inroads into the water and wastewater industry – our main market – for some time. From our perspective, we have seen them win a lot of customers in the SE of the USA. They might be winning customers in lots of other areas too.. we’ve just noticed the SE region.

The Florida market has had a major supplier who locked up the customer base with a proprietary protocol. What Trihedral did was reverse engineer the protocol. As a result, the Trihedral VTS platform can be implemented by these customers who can continue to use their existing field hardware but are now free of their restraints! They change their SCADA platform, keep their old hardware (so don’t have to change everything overnight), but they can start using new products.

These customers who have switched to VTS can now introduce any product they want in the field – or the plant – so long as it supports open protocols like Modbus or DNP3. 

The Partnership

That’s the background, but the news item is about what Trihedral have done, in partnership with MultiTrode. VTS will shortly have an “add site” function for MultiSmart.

This function essentially removes a lot of the legwork, or integration, out of bringing a MultiSmart site with 100’s of tags (data points) into the VTS system.

The new version of VTS isn’t quite out yet – expected in February. But I saw a demo of it a few months ago and was very impressed. The MultiSmart pump station manager was on an ethernet link (could have been a radio link) to the VTS SCADA server and the whole process was automated.

The remote MultiSmart site created a compressed version of the XML configuration (we use XML as standard for all configuration files), transmitted it using DNP file transfer (industry standard), VTS loaded it, unzipped it, and presented the user with a few checkbox options for configuration – including graphics, alarms and controls.

I know some of the Florida customers are very keen to get their hands on it. And some of our engineers are very interested in what Trihedral have done.

2+2 is more than 4 – if you choose the right combination

That’s the beauty of working with other companies who are great at what they do and have a passion for making things better! New ideas that spur our engineers on to come up with even more innovation.. and make life easier for the customer. Read more…

SCADA & Telemetry Add new tag, DNP3, MultiSmart, SCADA, telemetry

This follows on from the first blog post on DNP3 where we covered Date/Time Stamping – or Less Guessing - and a little bit of a comparison with Modbus.

This post is about some of the mechanisms for communicating between the SCADA, or master station, and the remote site. By the way, in DNP3 speak, you often hear the term “outstation” for the remote site. We’ll tend to stay with RTU (depending on who you talk to it either means “Remote Telemetry Unit” or “Remote Terminal Unit”), which is essentially the device that communicates.

Polling 

Let’s start with a Modbus comparison again, just to give a little context. Modbus is a totally polled environment – that is, the master station (typically a PLC) requests data from a site. The remote site can’t choose to send some data to the master station, it has to wait until the master requests it. So a very typical arrangement for a collection system is where the master PLC polls each lift station in turn and when it is has finished, starts again.

This has a lot of disadvantages as anyone with a growing network of lift stations has found. The time taken to get around the network goes up and up. You might get to a point where it’s 15 minutes between polls and decide to prioritize certain sites to get polled more frequently, or add a radio frequency (and therefore a new base station and repeater radio) to split the network into more manageable pieces.

It’s not an ideal situation, because Modbus isn’t an ideal telemetry protocol. (It’s a great protocol for other applications).

Unsolicited Reporting

If waiting until the master station asks you how you are doing isn’t the best way, what about unsolicited reporting. What’s unsolicited reporting? The remote site, also known as the RTU, sends data to the master station without being asked.

If you are used to Modbus polling systems, this might sound like anarchy. And if you have every site sending a message every time an event takes place, it could well be anarchy. Will the radio network stand up to lots of sites all trying to communicate at once?

The only way you might be able to prevent chaos, is by having a very limited amount of data getting sent, or a high radio bandwidth. One of the guys in MultiTrode told me about a system he was involved in with a previous company where they used unsolicited reporting for every event, and during a major storm the entire network shut down due to “collisions” in the radio network. The solution was for someone to go and visit every site and reset each RTU. Then the network started communicating again. But they lost all the data for their critical event.

That’s not great. What’s the solution?

Communication Choices and Different Classes

The DNP3 protocol has some great features to avoid the problems above.

Firstly, you can group events into different classes. Then secondly, you can choose how those different classes communicate from the RTU to the master station.

An example is the best way to explain it. Suppose you want to know about all high level alarms within 1 minute, and otherwise you are happy for all stations to be communicating at least once every 30 minutes.

You would put the alarm “High level” into class 1, and everything else into class 2. Then you would set class 1 to unsolicited reporting immediately. And class 2 you might set one of two ways – either to report every 30 minutes or sooner if the event buffer was full; or you might have the master station polling every 30 minutes.

Now you can find out immediately about high level alarms without risking the network turning into treacle and you still find out about all the changes in your network.

It’s the flexibility in DNP3 that is one of its great features. As Paul Gibson, one of the key people behind the development of the MultiSmart pump station manager, said:

“If we didn’t have DNP3, we’d be trying to design a protocol just like it to put into the product.”

The Communications Network still needs Design

Just because there’s a flexible protocol doesn’t mean you don’t have to do anything. Every communications network needs design. How much data? What is the bandwidth? What are the delays?

Read more…

SCADA & Telemetry DNP3, Modbus, MultiSmart, RTU, SCADA, telemetry

In the water and wastewater industry in the US, Modbus is the most common telemetry protocol. Its great benefit is its simplicity – and almost everyone in automation and process control is familiar with it.

For a few years now, we’ve been promoting DNP3 for telemetry instead of Modbus. Why? What’s the benefit? For people new to protocols and telemetry it’s hard to know where to start. 

Today, we’ll cover the first benefit:

Date/Time Stamping – or Less Guessing

DNP3 adds a date/time stamp to every event when it occurs. Each event is added to the “event buffer” in the RTU with its own date/time stamp. Then when the RTU communicates with the SCADA, or “master station”, the data can be stored in a Historian (database) or displayed on the HMI with the actual time the event took place – not the time that the master station received the data.

I mention that point because a lot of SCADA systems, most of them, were so orientated around process plants with hard-wired high speed data connections (like ethernet or high speed serial) that the normal mode of operation was to log the data with the date/time that it was received by the SCADA (and ignore any date/time stamp from the field if one existed). It doesn’t matter too much in a process plant – the comms is almost instantaneous – and if any comms outage occur they are quickly fixed.

DNP3 tells you when the event occurred – not when the SCADA system found out about it! 

In wastewater collection and water supply systems almost all of the assets are distributed in the field. And communications are often disrupted. Even when they are not disrupted, you don’t want every event to be communicated when it occurs.

Here’s how a typical Modbus network works – the master station (typically the master PLC) “polls” each site in turn to get all of the current data.

“Get the current data” means read a snapshot of all of the Modbus “registers” or data points. Most of them won’t have changed, so you are using precious bandwidth to capture lots of unchanged data. What about the data that has changed? Unfortunately, you don’t find out when it changed. You can just see that a different value is there now.

Modbus fills up the bandwidth with data that hasn’t changed. DNP3 only captures the data that has changed. So it can communicate a lot more useful data in the same bandwidth.

Let’s use the example of an analog process value. The value that the SCADA last captured from the field was 6.8, this time around – 10 minutes later – it is 6.9. So when the SCADA trending client displays this value – or you produce some kind of report, the process shows 6.8 moving to 6.9. Is that what happened? Or did it go to 7.1 and then back down? You’ll never know. You might know your own process really well, or you might be guessing.

You might know your own process really well, or you might be guessing. Using DNP3 avoids the kind of detective work that often goes on, where the operations and engineering staff try to fill in the gaps!

And then lastly, what if comms to that site – or a number of sites – is down for 24 hours? With DNP3, when comms is restored, all of the events during that period will be communicated to the SCADA (check out the technical note below).
 

Do I need this?

Whe you build a house, if you have the right foundations and structure you can add another floor. If not, you have to knock it down and start again.

To begin with, just getting reliable data out of a SCADA system is a great relief. But once it’s working and providing data you start to ask more questions – because you want to make the system work better.

Did both pumps run together in Pump Station 18?
What’s the hydraulic delay between Station 19 and 18?
I know the radio failed but do we know how high the level got at Station 12? And so on.  

A Quick Technical Note

Designing your comms system always takes some work and this isn’t aimed to be a technical workshop. But one important point with your field device is to ensure that the event buffer has been configured with enough memory to capture all the data that you might need in an outage. And the other important point is to ensure that the DNP3 configuration is for SOE (sequence of events) – as it is possible to configure last event only.

I mention these points because it is often only when you really want the data that you find out it wasn’t configured to capture that data that you wanted. Best to check when starting out.

Learn More

There are two whitepapers about DNP3  on the main site. One covers DNP3 Security – “Keeping SCADA systems open and secure from cyber-attack” and the other is more general – “Benefits of DNP3″.

To access the whitepapers you do need to complete a short registration form.



Read more…

SCADA & Telemetry

Like most other businesses faced with the challenges of today’s recessionary climate we recently brought our management team together to work through some scenario planning. I would recommend the exercise to anyone looking for strategic preparedness. In the course of the workshop we reviewed the overarching trends influencing the water and wastewater industry.

No matter what the economic situation the owners and managers of water infrastructure all face similar challenges. There are intersecting trends driving what happens in the market.  These trends are not going to change because of the current recessionary economic pressure on global markets. In fact it’s my view that we will now see them become more defined and more instructive .

Environment

The first trend is one of increased regulation. Around the world we see this trend gathering pace. This includes higher standards for drinking water quality and zero tolerance of waste water spills and strict monitoring requirements by the regulators.  Here is a truth: After every crisis the amount of regulation increases.  So after the dust settles on this global downturn expect a rush of regulator activity.

Security

The next is the post 9/11 concern over security of remote telemetry communications and control at water sources, treatment plants and pumping stations. This was once the domain of a few passionate souls who were almost being treated like Henny Penny, the character that claimed the sky was falling. Now it is an agenda item for most Homeland security agencies around the world. And people are beating a path to Henny Penny’s door.

Infrastructure

Thirdly our aging water infrastructure requires a steady investment. In most of the developed world water and sewerage infrastructure dates back to the years just after World War Two.  It has suffered from chronic underspend and a rapidly increasing population. There is a huge gap in what is presently allocated to be spent and the rate of spending needed. In the United States alone the estimate is a spending gap factor of ten to one.  No wonder that the rate of investment in water has been increasing in popularity.

Workforce

On top of this our workforce is changing. As people retire and exit the industry we are finding it harder to attract the number of good talent to the water business. Its not that we don’t have the talent in the new recruits – it’s that there are not enough of them.  This has focused the industry on seeking productivity outcomes. We now reward anything that lowers the capital costs and operational budgets and provides a knowledge foundation for replacement of technical staff. Even if we see an easing in the job market as a result of lay offs now that the greater part of the world is in recession the rate of growth potential for water infrastructure will soak it up quickly. Skills shortage is here to stay for some time.

Technology

The final trend that meets at the intersection point is the increasing use of low cost smart embedded devices that can be located remotely and linked using modern communication protocols.   This technology is small, full of application specific firmware, that can self-diagnose and are packed with high end communication capabilities. Plenty of multinationals like Schneider, Emerson, Siemens are putting big bets on this area but the water challenge is so great that there remains a huge opportunity for niche companies like ours to outperform the majors with highly targeted offerings.

My challenge now is to ensure I keep the company very close to the customer and these trends. I have set certain priorities for the business and one of the most important is a renewed focus on what keeps the customer awake at night. This blog is a company initiative designed to generate discussion and to share ideas. I will be keeping a close eye on the blog as it develops into a key source of communication with our customers and the community.

Read more…

Industry

A few years ago, we found that operators in a few wastewater utilities in one state were visiting their lift stations regularly – some once a week, others once a month, to pump the station right down to the snore point of the pump. It was an important maintenance task because pumping the well down as far as possible was a great way to clean out as much of the build up as possible.

The operators here found that the result was more reliable operation of level devices, less pump blockages and less need for frequent visits from the cleaning crew.

That insight led to a simple well clean out function in the MT2PC, and then in a more advanced form in MultiSmart. The MT2PC version just allowed for a periodic pump down, every so many cycles for so many seconds. Customer feedback from the MT2PC feature was that some improvements could be made -which we couldn’t put into the MT2PC - but of course we did implement these improvements in MultiSmart.

How does it work?

The idea is that periodically, when the well level reaches the normal lead pump (duty pump) OFF point the pump down cycle is extended a little.

Optimize Station - MultiSmart

The MultiSmart feature allows the choice of how to initiate this extra pump down – after a set number of cycles (e.g. every 100 cycles), or on a timer. If you choose timers for the well clean out you might set Monday between 8am and 1pm. If it was a very slow moving well and the OFF point wasn’t reached within this time, the well cleanout wouldn’t happen. Normally of course the OFF point would be reached within this time window and so the cleanout would take place - but only once. The advantage of the timer over using number of cycles is that you can make sure it takes place when people are at work – in case there’s a problem.

Should we introduce “Stop on under-current”?

There was a third choice for the well clean out that we think is a good idea but it hasn’t gone into the product yet (as of writing this post) – run the pump on until under-current - i.e. until the pump starts to snore. In a way you can use this already, but you’ll get an under-current alarm!

If you think that this would be a useful feature for you – or you have any other comments about this feature or the practice of cleaning out wells – please comment (below)!

How is it setup?

From the Settings menu, on the first screen you see Station Optimization, select that and  Optimize and you’ll find the well clean out function with all the parameters. You’ll find some other useful features there as well.

Disabling the low level alarm is managed from the level alarms in the advanced menu:  Advanced – Pump control – Well – Well 01 -Level alarm -Low level – Well clean out disabled (check the box). You might have a low low level alarm as well, if you do you should do the same for that alarm.



Read more…

In the well

If you’ve visited our site before, welcome back, and if you’re a first time visitor to multitrode.com, thanks for stopping by.

Why do we have a new site?

The previous site was running since 2002 and was on a technology platform (for the techies – Cold Fusion) that made it hard to do some new things we wanted to do.

Just about everyone’s familiar with that problem – usually not with running a website – but having an out-dated system slow us down or increase our workload. Most of our customer base has the frustration of large parts of their infrastructure being old and out-dated – sometimes all of it. In a recent survey we did of Florida utilities, ageing of existing infratructure was considered much more of a problem than managing any growth of the system. And across our major markets of the water & wastewater utilities in the US, UK and Australia it’s something we see every day.

The Blog

The Blog is something new for us as a company. A lot of people are very familiar with blogs, and for them blogs can often be their main source of information. For many others, the response is more “what’s a blog?”

Blog stands for – is short for – “Web log” – but really is a more informal way of communicating with the outside world.

Press releases, by their nature, tend to be fairly formal exercises and only communicate a small subset of what we would like to be saying to our customers and partners around the world.

So the idea behind us starting a blog is to have more frequent and richer communication with all the people we work with.

There’s two more great advantages of a blog – they allow and encourage responses; and it’s easy to subscribe to a blog so you can read updates, without getting your email box full of stuff you haven’t got time to read.

Let me explain a little more

If you’re like me, you use your email inbox as a tool for managing a lot of your action items. People you work with, inside and outside your company, email you and expect responses. If your inbox fills up with possibly interesting news from outside companies you get frustrated and start deleting it – even though you might want to read it if you just had a few minutes.

So getting too much email is one of the frustrations of modern working life. We’ll try not to send too much to your inbox!

Another way of keeping track of what’s going on is visiting a supplier or partner’s website every once in a while to see what’s new. It’s hard to remember what was there last time. How do you find the new content? Maybe there’s a press release about a new product or an update or a new service or a case study – but maybe there isn’t. There’s a great tool for keeping track of news, and the techies amongst you will have been using it for years. I only really started using it about 12 months ago – a news feed program.

Google Reader is what I found so easy to use, and now I can’t understand why I didn’t use newsfeeds long before. What does Google Reader do?

Basically it takes all the new content from all the websites and blogs that you subscribe to and puts it all into one place. So instead of you visiting the websites of 5 newspapers, and trawling around looking for interesting stuff, instead you can just get all of the news stories you want delivered to the reader. Maybe it doesn’t sound that great, but what you find when you start using it, is you can keep up to date with information from 50 sources very quickly. I’m currently subscribed to over 40 feeds, some of them work related, some are personal interests, and the new stuff just arrives. Some of the feeds I hardly look at, others I read most of the posts and sometimes follow all the discussions that follow if I have time. When you realise you aren’t interested in a news source any more, you just click “Unsubscribe” and it’s gone.

You can check out Google Reader very easily – at www.google.com/reader – all you need to do it create a Google account if you don’t have one, and then search for some news feeds. There’s lots of other readers around, for more on the subject take a look at the Wikipedia article: http://en.wikipedia.org/wiki/Aggregator

How do you subscribe to a news source?

Usually you look for RSS (Really Simply Syndication) or a feed symbol on a webpage (see the top right of this page) – or you can simply search for the site from Google reader. When you see the RSS or feed symbol on a site you click on it and it usually offers to add the newsfeed for that site to a number of readers, including Google Reader.

Click on the +Google button..

Once you click on the Google Reader button on the right, you’ll be subscribed to that newsfeed or blog.

Try it, or any other news feed “aggregator”, and you’ll start to find that it’s the place you go to get the information you want.

Hope to see you back at the MultiTrode blog soon, there’s plenty going on that we want to share with everyone. Read more…

General News