How to Monitor Your Telecom Batteries 7x24x365

Let's walk through the reasons for high-quality battery monitoring. We'll look at the the inherent difficulties. We'll also review one possible solution that walks the line between "ineffective" and "too expensive to justify".

Your batteries MUST be protected

UPS batteries for telecommunications systems are used in many industries:

• Telecom
• Electric generation & distribution
• Transportation
• Police/Fire/EMS radio
• Government & military

The BVM G3 uses newer D-Wire sensor technology to monitor 3 key battery values at once: voltage, temperature, and internal resistance. I include more details at the end of this article.

In their own ways, each of these industries protect human lives. That makes every remote site they use in telecom applications absolutely critical.

UPS battery strings are used as a backup power source to keep telecommunications equipment online at all times. This protects you when commercial power fails. That makes them just as deserving of protection as the communications equipment they power.

You need good remote visibility of your batteries to protect against:

• Sudden battery failure.
• Thermal runaway.
• Undetected normal discharging that eventually drains your batteries completely.
• Long-term reduction in battery life
• Gradual deterioration that leads to internal shorting.

Some monitoring solutions just don't work

Unfortunately, monitoring your batteries isn't always easy. There are plenty of optons that won't do the job, for one reason or another.

Scheduling recurring visits with a handheld tester is a waste of time and money. Your skilled technicians have much better things they could be doing. They shouldn't be driving for hours just to check on remote site UPS batteries. This also can't protect you from sudden failures (full discharge, thermal runaway) at sites you don't visit extremely often.

Buying expensive monitoring systems that are impossible to justify will never work. I've heard from many DPS clients a common (entirely serious) comment.

"For the price of most battery monitoring systems, I'll just replace the battery strings more often," they say. Perhaps that's an overreaction, but there's no doubt that budget constraints are real.

What you can never forget, though, is that the people you serve need your services to be 100% reliable. Replacing batteries is hardly the only cost of a service outage.

For that reason, not monitoring at all and having to replace your batteries will not work. Even if that's the "right" choice in the face of ultra-expensive monitoring systems, it's still wrong. With equipment failures, you have to price in the risk and impact of service outages.

You won't just be replacing a battery string. You have to contend with upset (and possibly lost) customers. If you work in "government" or telecom, the lives of your "customers" (residents) might actually depend on your network reliability.

Your shopping list for high-quality battery monitoring:

So, what DOES work for keeping track of your battery status? The right solution will help you solve the problems above without dooming you to the pitfalls above.

Whatever battery monitoring system you choose, make sure that it:

1. Monitors the "Big 3" elements of battery health: voltage, temperature, and internal resistance.
2. Provides 7x24x365 protection - without requiring repetitive site visits.
3. Is reasonably priced, but also highly reliable. Look for a manufacturer with a history.
4. Is adaptable to your battery types, whether they're 12-volt, 2-volt, or some other voltage. You should also be able to handle lithium-ion batteries, AGM batteries (Absorbed Glass Mat batteries), or thin-plate-pure-lead batteries.
5. Takes advantage of the opportunity for monitoring efficiency. Sure, you have to monitor your batteries, but what about fuel levels, equipment alarms, door sensors, and everything else? If you pick the right system, you can monitor every important thing within your remote telecommunications facility with one box.

Recent Solution: The BVM ("Battery Voltage Monitor") G1 & G2

These are the considerations I had in mind when I helped the Engineering team here at DPS. We revised our BVM ("Battery Voltage Monitor") system into the G3 model.

The birth of the BVM was, as the name implies, focused around voltage only. The device had 24 analog inputs for monitoring up to 24 cells. You simply wired leads to each battery in the string. That was great, but what about thermal runaway?

The BVM was originally conceived as a voltage monitoring device, but it has evolved twice since then to add temperature and internal-resistance monitoring.

The BVM G2 incorporated temperature monitoring and our newer "D-Wire" sensor technology to support daisy chaining. You'd place one on each battery to get BOTH voltage and temperature readings. The gear is also 100% DPS-manufactured, giving us more control over quality.

This was a big improvement, but the D-Wire bus had limited power for running a lot of sensors. This was fine for 4-battery strings, but 24 batteries became unworkable. Also, the temperature sensor, being in the aluminum sensor chassis, had some moderate lag in detecting temperature spikes.

Solution Example: The Revised "Battery Voltage Monitor G3"

In 2020, I helped DPS Engineering to create a new BVM model. It would address "really serious battery monitoring", which encompasses long-term battery health. You can't simply detect this with voltage and temperature. You need more.

Like any good successor, the BVM G3 added a new measurement: internal resistance.

It sends brief pulses of AC through a battery every few minutes (or even hours). You get an updated reading of how much power is lost to internal resistance. This tells you whether you have internal cells that are starting to fail and short.

The BVM G3 is:

• A system that will perform continuous battery checks on your batteries (2-4 battery strings at typical sites). It shouldn't require site visits and time spent putting on clamps and downloading data. It provides automated continuous battery monitoring with sensors connected directly to each of your batteries. Temperature, voltage, and internal resistance is monitored for each battery.
• Alarm and status reporting to your existing T/Mon LNX or any SNMP manager.
• A monitoring device that is independent of your existing RTUs, but that can also monitor some external equipment and sensors if needed.
• A device that you can easily manage via its built-in web interface.

The BVM G3 uses newer D-Wire sensor technology to monitor 3 key battery values at once: voltage, temperature, and internal resistance.

The choice is yours

You have to determine which battery management device you want to purchase and implement in your network. I've given you a general outline of criteria you can apply when talking to any manufacturer or vendor.

DPS engineers and I designed the BVM G3 to be well-suited to real-world concerns you're likely to face. Only you can make the call.

If you'd like to evaluate a BVM G3 or other monitoring device, just give me a call (559-454-1600) or email DPS: sales@dpstele.com

Andrew Erickson

Andrew Erickson is an Application Engineer at DPS Telecom, a manufacturer of semi-custom remote alarm monitoring systems based in Fresno, California. Andrew brings more than 17 years of experience building site monitoring solutions, developing intuitive user interfaces and documentation, and opt...