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Ensuring your alarm survives load shedding

While some parties, including certain divisions of the SAPS may claim that load shedding has no tangible effect on the number of burglaries occurring, it would seem that the criminals are definitely capitalising on the scheduled lights-out programme. Naturally, when the electricity supply halts, batteries powering intruder detection systems and other security systems are put under pressure. This is exacerbated when load shedding picks up pace.

The solution, according to Jack Edery, CEO of Elvey, is to consider the implementation of a backup system for the battery. “We know that the criminals have a nicely coordinated list of areas experiencing load shedding so we need to prevent them from utilising battery down time as a reason for entering properties unlawfully.”

The South African Intruder Detection Services Association (SAIDSA) says that no power means that the security system is running on a battery that is no longer charging. “This is fine in the short term, provided that the battery in question is still 100% efficient. Unfortunately, frequent power cuts, cable theft and load shedding have a detrimental effect on batteries and reduce their lifetime.”

They continue that many lower quality batteries, when fully discharged, do not always recover from a total discharge. “This in effect means that thousands of intruder alarm systems in South Africa are literally running off their transformers, particularly in older systems.”

Edery says that reliability becomes a driving factor when considering intruder detection systems and any system is only as good as its reporting system and backup. Since power surges negatively affect battery life and reliability, and the average backup time of a healthy battery is between three and six hours, he suggests investing in a combination of technologies geared around ensuring that intruder detection units are maximised for performance.

The alarm standby battery extender is a 5 Amp 12 VDC backup switch mode power supply that, when connected to the alarm’s battery, ensures maximised uptime of the battery to keep the system operational even during extended load shedding or unplanned outage periods.

The low battery radio cut-out module protects the alarm system’s backup batteries from being discharged below 10.6 V, where RF signalling devices (RDC radio) is connected directly to the battery. This results in prolonged life of the battery and ensures that the backup battery is automatically restored to full load when the charger voltage is restored.

The low frequency pure sine wave combined inverters and chargers marketed by Elvey are silent up to 3 kVA, thereafter there is a slight noise from the fan. Unlike generators which incur ongoing fuel costs, inverters are subject to a once-off purchase price with no further costs involved. While inverter batteries have a lifespan of between one and 15 years under float service, the real difference is that the only time you need to attend to the batteries is when they need to be replaced.

These IBT series inverters convert low voltage battery current to high voltage mains power, for uninterrupted power supply to the alarm system and other critical circuits such as some lights. The inverter manages the cycling (charge and discharge) of the batteries to maximise the life of the battery. Edery advises that a cool storage area is recommended.

Edery points out that the company makes use of easy to use calculators to ensure that the batteries being supplied deliver an effective standby time, based on the total load requirements. He comments that if a solar and power backup system is well designed, it can be built up in affordable stages. The system could begin with ensuring a steady power supply to the alarms, CCTV, access control, fire, electric fence and gate motors of any home or business security system. The solar energy will allow the natural charging of system batteries with an inverter in place for load shedding periods.

Ultimately, a security system needs to remain completely active even during extended load shedding periods. By consulting with a company like Elvey, installers are able to devise a customised solution that ensures that all systems remain active.

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