TECHNICAL
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mobile banking solution . The token arrives as a 20-digit numeric number , which is entered on the Customer Interface Unit ( CIU ), situated inside the house .
Between the periods 2004 to 2015 , prepaid meters were tasked to deliver Free Basic Water ( FBW ) at no cost to consumers . FBW was delivering 6 000 litres of water per month at no charge to those who cannot afford it , but with the option to purchase more . A great initiative , but more and more municipalities realised it is just not affordable . The more technically-minded gurus quickly realised this very same feature can be used to configure the prepaid meter as a Demand Controller . The consumer is still using his conventional meter , billed monthly , now being fitted with a prepaid controller , configured to only deliver a daily limit of , for example 350 litres before the meter closes , with no means to purchase additional credit . The meter will only re-open the next day . And “ voila !” you cannot exceed your daily allowance – it does not matter how much money you throw at it .
Leak Detection is another great and mostly overlooked feature when it comes to water conservation . The prepaid controller records the lowest hourly flow measured , typically during the early hours of the morning between 1am and 3am . If over a period of 24 hours , a continuous flow was recorded for every hour , it can safely be assumed that there is a leak on the property . The lowest hourly flow recorded equates to the size of the leak in litres / hour .
The ‘ Life-line ’ feature helps to prevent you from running out of water at the end of the month when you do not have any money to purchase water . Activating your Life-line , allows a preconfigured amount of water per day , while at the same time running your credit register into a negative value . When you have the opportunity to purchase more water credit , your negative credit is replenished first , before returning your meter to positive credit .
With the invention of low-power , long-distance wireless networks , remote monitoring has become a reality for water meters . South Africa is the proud owner of a dedicated low power network , implementing Sigfox technology , covering 93 % of the population . This technology allows a battery-operated meter to transmit data over very long distances . Specifically targeting metering applications , this network allows water meters to send totaliser readings and other diagnostic information on a daily or even hourly basis while still maintaining a 10-year battery life .
It is now possible for utility companies to receive conventional meter readings for billing purposes over the Sigfox network directly from their meters . Connect the SmartWater AMR ( Automated Meter Reading ) device to any conventional meter with a pulse output , and receive the totaliser reading daily . Never again do you need to go out and read the meter or calculate estimates . PA
Telbit is a key component designer and manufacturer to Sensus ( Part of Xylem ) and Elster Kent ( Part of Honeywell ).
Telbit
Typical prepaid installation .
“ The homeowner wins , the body corporate is in the green with the municipality , and the utility company is running a viable business .”
April 2021 Volume 27 I Number 2 www . plumbingafrica . co . za