Battery Monitoring – Questions and Answers
Recently Jantech Services, Inc. had a Vendor Booth at the Critical Facilities Summit Conference in Charlotte. This was a great show and conference with more than 100 Vendors participating in the trade show hall.
Of particular interest to us at Jantech were the questions we were asked with regard to battery monitoring, primarily we believe, because there were at least 5 Battery Monitoring Companies displaying their wares, discussing why battery monitoring was needed and why their solution was the best.
Questions included: Do I still need Battery Maintenance if I have a monitoring system? Which battery monitoring system is better for my UPS batteries? And, does it make sense for me to have a battery monitoring system at all, especially if I have either a single battery cabinet or multiple battery cabinets for each UPS module?
To Jantech, there is no singular answer for any of the questions, the subject of battery monitoring has been quite controversial for years and still is today. At conferences such as BATTCON (Major battery conference held every year) discussions and papers are presented that continue to debate the best way to actually do the monitoring and the accuracy of the predictive modeling results.
Any battery installation regardless of type or chemistry will fail at some point. What a battery monitoring system can do is help extend the time between replacements, not extend the life as has been claimed. Replacement of the battery will usually be done based upon the recommendation of the battery maintenance company, the policy of the end-user and how risk averse they are.
Short answers to the above questions are:
1. Do I still need Battery Maintenance if I install a battery monitoring system?
Battery Maintenance is still required, a battery monitoring system is another tool in the toolbox of battery maintenance. Examples of items that most battery monitoring systems do not take into account include: corrosion, inter-tier cable connections (contact resistance and connection tightness or cables between the battery and the batter breaker/ disconnect (contact resistance and connection tightness).
2. Which Battery Monitoring System is better for my UPS batteries?
This is a tough question to answer. Most of the battery monitoring systems utilize battery ohmic values (impedance, resistance or conductance) measurements plus other measurement parameters to compute and display data that can be used for trending and predictive end-of-life. The real answer depends upon your specific application, whether the monitoring data will be used/ reviewed daily and what you are trying to accomplish.
3. Does it make sense to have a monitoring system at all?
This truly is a site specific question, and is based upon many factors including:
i. Does my monitoring system cost more than 1 or 2 battery replacements? For single cabinet VRLA systems this can be the case.
ii. Since I have multiple battery cabinets why not do a replacement of 1 or 2 battery cabinet of batteries every year.
b. Criticality of the load
i. Any system that can provide additional data about the trending of my battery will allow me to make a more educated decision (if used and interpreted daily)…remembering of course that monitoring is neither prevention nor maintenance.
c. Replacement based on age and physical environment
i. With the quality of today’s VRLA batteries many customers have chosen to utilize this method, especially when looking at the economics.
With Jantech Services being vendor agnostic we are in the unique position of working with clients going through this process.
It should never be forgotten that a Battery Monitoring System does not replace battery maintenance, rather it can enhance a maintenance program. A combination of a trending state of health data stream based preventive maintenance program is optimal for battery performance and life. However, this is the area where the 28 years of experience and expertise of Jantech Services is required.