Auto dialers have a long history of providing notifications in remote SCADA

(Supervisory Control and Data Acquisition) installations. Most auto dialers detect

possible alarm conditions by using discrete digital and analog ports connected to

sensors. Once a problem is detected, appropriate users are notified when the

device calls one or more pre-defined phone numbers to report the alarm

conditions.

While auto dialers are in some cases an effective way to remotely monitor pumps,

valves, motors and switches, the evolution of SCADA installations have resulted in

more complex equipment on site that needs to be monitored and controlled. There

is also a greater demand by SCADA users to optimize operations by automating

functions that can be done remotely in order to eliminate the costs and time

required to send a technician on site to verify the existence of a problem, diagnose

the root cause and plan for remediation.

In this white paper, we will explore how SCADA installations can evolve from the

use of auto dialers to a more comprehensive way of managing remote sites that

increases visibility while reducing the costs.

SCADA technology is used in a number of industries including the oil and gas,

electricity, and water and waste water industries. It is used to monitor and control

equipment of all sizes and complexities. SCADA systems gather information such as

pump on/off events, liquid flow, water levels, pressure values, and temperature

readings and send them to a central management system.

Traditionally, SCADA system operators were looking for confirmation of basic

functionality and to be notified when abnormal events occurred. Examples of

events include:

- Levels above/below predetermined thresholds

- Pump/generator on/off events or excessive starts

- Intrusion detection

- Power loss

- Temperature readings or pressure values above/below thresholds

These types of events are easily reported by simple auto dialers using conventional

phone lines to report when values have crossed high or low set points.

However as SCADA systems have evolved and operators increase their demand for

information; some data cannot be easily communicated using auto dialers over

analog phone land lines.

Wireless communication has enhanced the possibilities when it comes to SCADA

monitoring. Operations managers are no longer restricted to relying on auto dialers

connected to phone lines for communicating SCADA events.

Operations managers can now have more physical reach by being able to monitor,

control and automate equipment located at remote sites spread over large

geographical areas. It has also been part of the evolution that allowed customers to

move away from closed, analog connections to digital and IP (Internet Protocol)

based systems.

As technology has evolved, SCADA remote monitoring and control equipment like

PLCs (Programmable Logic Controllers) and RTUs (Remote Terminal Units) have also

become more feature-rich (and complex). The increase in proliferation and

functions in PLCs and RTUs means there is a greater richness in information

available locally to operations managers. However, the challenge is to exchange

information with the equipment in a timely manner and make it available to the

SCADA master station and HMI (Human Machine Interface) for viewing,

interpretation and driving business KPIs (Key Performance Indicators).

Whether you are building a new remote SCADA site or retrofitting an existing site,

there are many points to consider so that you are able to extract richer

information. Building (or upgrading) a successful SCADA network depends not only

on understanding today’s remote monitoring and control requirements but

implementing a system that can scale to tomorrow’s needs.

Beyond the master station, there are three main components of the SCADA

network that need to be selected when looking at the architecture of the SCADA

network. These are:

1. Controllers or Data Terminal Equipment (DTE) at the remote sites

2. Data Communication Equipment (DCE)

3. Communication (telemetry) network

Today’s controllers, whether they are PLCs, RTUs or intelligent communication

terminals, come in various sizes and capabilities to meet master station and remote

station control needs. Here are 10 things to consider when selecting this type of

equipment:

1. Local Intelligence and Processing: Is the unit programmable? What is the

processing throughput? What is the data logging capacity of the unit?

Cellular

network

Head Office/

SCADA HMI

SCADAconnect

Enterprise

gateway

Satellite

network

Telemetry data IsatData Pro

network

SkyWave

communication

device

SkyWave

communication

device

SCADAconnect

Asset gateway

SCADAconnect

Asset gateway Telemetry data

2. Input/Output (I/O) ports: What is the number of I/O ports and what is

their accuracy? Do they meet the needs of the application?

3. Communications: What telemetry communication services are supported?

Are there provisions for redundant communications for critical

applications? Can data be sent and received at a frequency required by the

application and the operation manager?

4. Protocols: Does the unit support open standard industry protocols like

Modbus and DNP3 on serial and TCP/IP ports?

5. Interfaces: What interfaces are required to connect to DCEs?

6. Power: What are the power requirements of the units? Can the unit be

operated on battery alone? What are the options for backup power?

7. Enhanced Security: Does the equipment support password-protected

programming, authentication and IP firewall capabilities?

8. Durability and Ruggedness: Is the unit rated to handle the temperature,

humidity, vibration and electrical conditions found at the remote sites?

9. Modularity: Is the unit expandable as demand and needs change?

10. Space and Installation: How much space is required by the controller and

how will it be installed at the remote site?

SkyWave Products as Data Equipment Terminals for unmonitored SCADA sites

In some applications, SkyWave satellite devices are a very cost-effective way to add

a controller with communication capability to a remote SCADA site. The IDP 600

series terminals feature four (4) general input/output ports for connecting analog

and digital sensors. The terminals also have RS-232 and RS-485 ports for connecting

devices that communicate via serial protocols like Modbus.

The onboard processor on the devices allows customers to program logic into the

device to react events like “Send a notification when the water level is above the

analog high threshold” or “close the valve when pressure reading is below low

threshold”. This “edge analytics” capability reduces the amount of data that is sent

wirelessly, thereby decreasing the time to react to events as well as monthly

airtime costs.

Learn more about IDP 600 series terminals at www.skywave.com.

SkyWave Solutions for SCADA sites with PLCs and RTUs

For SCADA sites with PLCs and RTUs, SkyWave offers SCADAconnect - a three-part

application that includes an asset gateway that quickly and easily connects to

remote PLCs and RTUs to extract data; a communication modem for relaying data

from remote sites to enterprise applications; and an enterprise gateway to

interpret the data from remote sites and insert them into the SCADA HMI (Human

Machine Interface) system.

The asset gateway allows customers to not only extract data from the PLC but also

to provide the edge analytics portion where only relevant information is sent to the

SCADA HMI system. For example, an operations manager can be notified only when

the fan speed changes by 5%. Anything below that would not be reported, thereby

reducing communication costs and “data overload’ syndrome.

Learn more about SCADAconnect at www.skywave.com.

DCEs are responsible for the exchange of appropriate data between

controllers/DTEs and the master station using the communication network. DCEs

include auto dialers, as well as radio, cellular and satellite modems and terminals.

Here are 10 things to consider when considering DCEs for SCADA sites:

1. Availability: Which communication networks are available at the remote

sites will drive the selection of the DCE. Options include radio, private

leased lines, cellular and satellite.

2. Redundancy: Does the DCE have redundant communication options?

3. Data Requirements – Does the unit support the transmission of analog,

digital and/or serial data?

4. Data Communication Rate: How much data needs to be sent to and from

the remote site? Will the data demand change as the site grows or evolves?

Can data be sent and received as frequently as required and desired?

5. Transmission Modes: Does the site need half-duplex or full-duplex

capability?

6. Response time and Latency: How much time does it take to relay

information between the controllers and the master station? Does it meet

the needs of the application?

7. Interfaces: What interfaces are required to connect to the controllers?

8. Standards and Certification: What communication standards need to be

complied to operate in that region?

9. Power: How much power is required to operate the DCE? Can the unit

revert to backup power in the advent of a failure on the main power line?

10. Durability and Ruggedness: Like the controllers, is the unit rated to handle

the temperature, humidity, vibration and electrical conditions found at the

remote sites?

SkyWave Products as DCEs

An integral part of SkyWave technology is the ability to provide cost effective

satellite communications for remote sites requiring the ability to send notification

of events and alarms as well as regular telemetry data. Since the system uses the

Inmarsat satellite constellation, customers who opt for this solution have the ability

to send and receive as much data as they want without being constrained to using

time slots at specific times of the day. They also receive the information in seconds,

rather than minutes or hours.

The IDP 600 series satellite-only devices are

rugged and compact. They are designed to

be installed outside and are also available

with C1D2 (Class 1, Division 2) certification

for use in hazardous locations.

The IDP 700 series satellite-cellular devices

are equipped with more than 17 I/O ports and can send information via satellite,

cellular or both, depending on need.

See satellite and satellite/cellular devices in action at www.skywave.com.

IDP-680 C1D2 Terminal

IDP-690 C1D2 Terminal

The communication network is the essential component for connecting remote

sites to master stations. When selecting the primary and secondary communication

systems, consider the following 10 things:

1. Coverage: Is the network available at the remote sites?

2. Uniformity: Looking at the entire SCADA system, is it important to use the

same communication networks across all the sites? Choosing different

networks depending on local availability will increase the number of DCEs

that need to be selected.

3. Infrastructure: Is there a need to install infrastructure like towers and

repeaters to support the communication network? What is the required

investment for infrastructure? Can infrastructure installation and

maintenance costs be outsourced to a provider like a cellular or satellite

communication provider?

4. Monthly Costs: What are the monthly usage costs?

5. Total Cost of Ownership: How does initial infrastructure and monthly costs

fit into company’s financial policies?

6. Reliability: What is the reliability of the communication network at each

remote site? Does it meet the mandated or desired service level

agreement?

7. Data Communication Requirements: How much data needs to be sent to

and from the remote site? Will the data demand change as the site grows

or evolves?

8. Transmission Modes: Does the site need half-duplex or full-duplex

capability?

9. Responsiveness and Latency: How much time does it take to connect to

the network and relay information between the controllers and the master

station? Does it meet the needs of the application? How frequently can you

poll or access data from remote sites?

10. Emergency Management: Does the communication network stand up to

extreme weather like hurricanes, tornadoes and tsunamis?

SkyWave Products and Communication Telemetry Networks

Think satellite is expensive? Think again. SkyWave devices are ideal for applications

that require cost-effective connectivity in remote areas where other

communication services are unavailable or cost-prohibitive to implement. In some

cases, customers who have chosen SkyWave solutions pay less than cellular

solutions.

In addition to costs savings, since SkyWave uses the Inmarsat satellite constellation,

data from SCADA sites are received within seconds, allowing operation managers to

react immediately to events. The system is also resilient to local weather events

like tornadoes and hurricanes since it does not rely on terrestrial towers.

Learn more about satellite solutions for your SCADA applications at

www.skywave.com.

The move towards increased visibility of at the status of remote SCADA sites and

collecting more data than provided by alarms (as offered by auto dialers) has

translated into significant cost and operational savings for managers. Benefits

include:

- Reduced field visits thereby decreasing labor and fuel costs

- Ability to schedule maintenance on equipment based on need, rather

than time passed

- Decreased MTTR (Mean Time to Repair) by receiving real-time alerts of

issues. Plus, being able to poll more data from the sites means being able

to diagnose the problem before dispatching a technician.

- Minimized downtime by being alerted of degradation in performance of

equipment

To achieve these results it is important to spend time considering the architecture

of your SCADA site including the Controllers or Data Terminal Equipment (DTE), the

Data Communication Equipment (DCE) and the Communication (telemetry)

network and how the solution can meet today’s remote monitoring and control

requirements but scale to tomorrow’s needs.

For more information about how SkyWave products can address your DTE, DCE and

communication telemetry network, visit us at www.skywave.com.

SkyWave Mobile Communications is a global provider of wireless data

communications for the Machine- to- Machine (M2M) market. SkyWave’s products

provide dependable communication, tracking, monitoring and remote

management of fixed and mobile assets. Over the past 16 years, SkyWave has

designed, manufactured and shipped more than 700,000 Inmarsat-based satellite

terminals to customers globally in the transportation, maritime, oil and gas, utilities

and government sectors. For more information, please visit www.skywave.com.

Inmarsat plc is the leading provider of global mobile satellite communications

services. Since 1979, Inmarsat has been providing reliable voice and high-speed

data communications to governments, enterprises and other organizations, with a

range of services that can be used on land, at sea or in the air. Inmarsat employs

around 1,500 staff in more than 40 locations around the world, with a presence in

the major ports and centres of commerce on every continent. For the year ended

31st December 2012, Inmarsat had total revenue of US$1,278 million and an

EBITDA of US$643 million. Inmarsat is listed on the London Stock Exchange

(LSE:ISAT.L). For more information, please visit www.inmarsat.com.