Hooking up alarm systems that monitor machinery, buildings and other assets to DMR radio networks is hardly an unusual occurrence today, but it is not as common as it might be.
“A lot of customers are not aware that alarms and alerts can be connected up to DMR radios,” points out Ian Hussey, technical sales manager at 2CL Communications. He adds many customers are unaware of how much more they can get out of a radio beyond just push-to-talk voice applications. This can include a software add-on for alarm management, capable of delivering audio alerts, SMS and emails in response to an alarm being triggered.
“The sales forces with radio resellers need to make these capabilities known to customers,” he says. “It is easy to take a gateway to a customer’s site and demonstrate how to connect an alarm to a radio, but until someone does it they don’t realise what can be done. If you do, you could end up selling 10 handheld radios, a software suite and an alarm connection package.”
The most common reasons for linking alarms to DMR radio systems are to increase the number of people capable of receiving the alert, easily achieved via the radio’s group calling feature, and, above all, to increase the speed of response.
“Take industrial automation,” says Steve Clarke, managing director of PMR Products. “The alert could be for something very serious, so what they want to do is cut out the old style of responding to an alarm and get the message straight to the guy on the shop floor who can react quickly to the problem.”
Kevin Golding, applications manager at South Midlands Communications (SMC), observes that the majority of jobs involve fire alarms because they are about life safety. The more sophisticated alerts send notifications not just that an alarm has been triggered, but the exact location and, where appropriate, what piece of equipment it relates to.
“Then you need to consider who to send the alert to once the alarm has been activated,” says Golding. “You can send a group message to all the radios, which is fine, but the trouble is you don’t know who has seen it and whether anyone is reacting.”
The advantage of (text-enabled) radios is, of course, that they provide two-way communications, so personnel are able to text back to say they have got the message. “More importantly, if no-one texts back within a set period of time, you can escalate the alert by sending more text or audio messages to radios, texts to mobile phones and emails to phones and PCs, or you can even fire off a siren,” says Golding.
A further refinement is the pre-alert fire alarm. “The customer works in conjunction with the fire brigade and gets permission so that if a possible fire is detected, it does not ring the fire alarm bell. Staff get sent a pre-alert instead. But you can only do this if you have proven to the fire brigade you have the people and systems in place,” says Golding.
One of the use cases for this is the hotel and restaurant industry. “If a fire alarm is activated, the hotel has to be evacuated, which is not good news,” points out Golding. Another is in schools, where kids break the glass on the fire alarm. If the location of the alarm is sent immediately, staff might be able to react in time to catch the child.
“We’ve had a good success with this in universities,” reports Golding. “It can really make a difference, as you can get fined for false call-outs to fire brigades. One university we know of clocked up a £200,000 bill for false call-outs.”
Interfaces
Once on-site, the first consideration is to find out what connections exist on the alarm systems and what connectivity solution might be appropriate.
Most new equipment comes with USB connections, which have largely replaced earlier interfaces such as serial ports and parallel ports. However, a lot of older machines and fire control panels are commonly equipped with RS-232 and RS-485 serial protocols, which are widely used on older industrial control equipment.
“It might be a traditional connection for a serial data port, which could be going to a printer, for example. There are a number of different standards,” observes Clarke. “If you can access that port and the information that comes out of it in a data stream, then within that data stream you can pick off pieces of information relating to alarms.
“So, as long as you know what to expect – this data is from pump machine number 5, for example – you can put a search in place for messages from that pump and convert them into text messages for the radios.”
Direct approach
Connecting these kinds of interfaces with DMR systems can be done either by directly plugging the DMR system into the alarm control panel or by using an intermediary gateway.
The chosen solution will largely depend on the competency of the dealer, notes Nick Vaas, technical services manager at Syndico, which distributes Hytera radio equipment and the SMC Gateway.
“If you take the direct approach, you need to know what the data stream is coming out and how to make it talk directly to the radio system,” says Vaas. “You probably need to be an accredited applications developer for the likes of Hytera or Motorola to do that.
“But only a few dealers have this accreditation, as it is a big learning curve and it has to be really worth their while to invest in it. You have to sign NDAs, get the API specifications, write your own software and so on. Some dealers do it, but it is a lot easier to just buy a gateway.”
PMR Products favours the direct approach and has developed its own software to do so. “We have a solution called SNAP (safety net alarm processor), which can be connected through a serial port,” explains Clarke.
“SNAP searches for streams of data that might be interesting, such as an error message, decodes it and then turns it into a text message, which in turn can then be broadcast to the DMR radios as a text message,” he says.
There are other ways of hooking up alerts to a DMR network. “You can use an IP-based interface, such as SNMP (Simple Network Management Protocol), which is an IP data protocol for sending out status messages. We created an app that looks for SNMP and have used that quite a lot for SCADA systems,” says Clarke.
Gateway approach
The other way of linking up alarms to DMR radios is to use a gateway or some other intermediary software solution. For example, South Midlands Communications’ SMC Gateway is now a widely used product.
“Our SMC Gateway is a hardware product with all the software built in. It’s a one-stop shop as everything is on there. You do not need PCs or any extra software, unlike some solutions. The gateway has serial ports and inputs and is software-ready; you just plug it in,” says Golding.
He points out the Gateway uses an embedded Linux platform, so there is no Microsoft software to keep updated and the DMR radio interfaces from all the manufacturers are embedded into the product. A GSM module can be added to send SMS messages to cellular mobile devices as well.
GlobalView Systems provides another alternative, as business development manager Richard Iveson explains. “We offer our R-LinX and InteraX solutions, both of which send alarms to DMR and which can also send SMS and email. The alerts will go to the required radio, or radio group, and can follow a predetermined escalation path. R-LinX is for smaller systems and InteraX offers multiple alarm listeners, with each following its own escalation path.”
On-site challenges
Everyone agrees on the importance of involving the alarm security manufacturer or provider when beginning the job. “One thing we strongly recommend is that the reseller maintaining the fire alarm to DMR system must collaborate with the fire alarm company involved,” says Golding.
GlobalView’s Iveson agrees that having early communication with the alarm installation companies will resolve most issues and stresses the importance of having their expertise on-site. “The lack of an available engineer [from the alarm supplier] will slow down the opportunity as many alarm systems require a port to be open/configured to enable us to link to the system.”
He adds a further tip: “As random unprintable characters can cause issues when trying to link a serial/printer port output to an alarm handler, early access to the protocol messaging is a great idea.”
If an IP connection is to be used then the customer’s IT people get involved. It is at this juncture that radio resellers can hit a buffer. “You get a mix of reactions from the customer’s IT people,” says Hussey. “Some are really helpful and keen to work with you, others won’t let anything on their network. I think the resistance we sometimes get is because they don’t understand, first, that you can hook up alarm systems to radios, and secondly, that if you have stuff going out over the air, it is not necessarily creating a weakness in their IT system.”
Hussey also points out that there can be some real upsides to getting security and fire alarm panel manufacturers onside. “They can recommend you to potential customers, and orders follow through. We have a large electronic security provider who now sells alarms and radios on our behalf, mostly for small sites with simplex operation.”
Legacy equipment
Another challenge facing installers is dealing with legacy equipment where the interfaces are very poorly documented, if at all. “We often have to send people on-site with a PC logger, which they plug in and record what comes out,” says PMR Products’ Clarke.
“In one instance we had to hook up to some furnaces, which had nothing obvious we could interface with. In the end we came up with an IP-based input/output module. We connected to the I/O panel stuck on the side of the furnace machine using an IP connection to the infrastructure. We then added our SNAP solution onto that.”
But what if the customer wants to connect to something more complicated than an isolated fire alarm system? Syndico’s Vaas says: “In the construction and property industry, there is a desire to link radios into advanced building management systems (BMSs).
“We’ve not seen any BMS systems that are easy to interface with radio. You can take data streams out, but not many people have written the software to do so yet. We tried it a year ago and got in touch with the supplier who said we can write some software for you to enable that, but it will be expensive.”
Security concerns
Security is another issue, as customers do get worried about connecting radios into their existing systems. Vaas reports that banks in particular can be wary to the point where dealers have had to get BT to provide a separate ISDN or ADSL line at the locations where they wanted to install the repeaters.
Firewalls are another issue. “If you do use the customer’s IT network, then you have to get the IT people to configure the firewall to allow the data traffic to pass,” says Vaas.
Allowing remote access to the customer IT system to enable monitoring of the radios, radio network and the alarms is, of course, highly desirable, but it can be difficult to negotiate agreement. “Network security is a major issue and some customers are reluctant to give you access and some won’t consider it all,” says Hussey. “But if you point out that over-the-air programming will save them money as they can update loads of radios overnight instead of having to pay for an engineer to visit, they can often be persuaded.”
“IT people used to get worked up if we connected to their external systems, but you can sidestep all that and keep it local,” suggests Clarke. “Implementing remote access using a secure router with VPN can be an issue for some customers. But you can give access to people on-site and they can be the key master if necessary.”
The future
So what of the future? The Internet of Things may still be at a relatively embryonic stage, but it seems logical that many industries might like to connect a wider range of equipment and process-monitoring M2M/IoT devices to radios.
This is being done to some extent already, as SMC’s gateway is being used to monitor a lot of different systems, such as the spray paint pot levels in a Honda factory, for example, and GlobalView’s InteraX software is designed to cope with more complex systems.
Syndico’s Vaas observes: “If manufacturers start embedding IoT in their products, the radio industry will have to learn it. We’ve been through the stage of moving from analogue to digital. We knew nothing about IP then, but we had to learn, so maybe now we will have to learn about all the IoT protocols.”
