Guest post from Ryan McKinnon - Northern Territory Sales
We had a customer that was working with a municipality to find out why their meter measuring their outflow from the reservoir was not reading correctly. The level in the reservoir was staying relatively constant, the inflow was also constant and the flow had been verified to be correct. The outflow was showing up to 4X the inflow rates, meaning the reservoir should have been dropping.
This started the discussion that the outflow meter must be wrong. We replaced the meter as per the customer's request and immediately had similar results to the first meter. The customer argued that the meters must all be wrong, so a technician was sent to the site to look into the situation. A clamp-on ultrasonic was used to verify the mag meter and was given very similar results (within a couple of percent). The customer still blamed the meter measuring the outflow and was looking at moving away from our products. A second trip was made with a separate ultrasonic meter to verify the mag meter. Once again the results were very similar.
We believe strongly in the technology that Endress + Hauser has developed. We have installed thousands of meters in Western Canada with spectacular results. The customer still believed that there was something wrong with the meter measuring the outflow and wanted to look an alternate technology. We explained that the chances of 4 meters now (original mag meter, second mag meter, first clamp-on ultrasonic and second clamp-on ultrasonic) would all be wrong but very close in their readings was not possible. Additionally, we had asked for all of the pump information and determined that the pump would be flowing very close to what the meters were reading based on the manufacturer's information.
We asked to take a look at drawings from the process. What we found was that the water from the reservoir was sucked out by a pump, from there was piped to the mag meter, the piping then went back down into the reservoir, through the bottom and when to the municipal trunk line. We suggested that there may be a leak in the line and that this should be checked. The contractor said they presented this to the municipal customer who turned it down initially (we have no way of verifying if they did take it forward). They had an investigation of the line completed and found that the line after the mag meter that went down through the bottom of the reservoir to the trunk line had a large crack.
This meant that the meter on the outflow line was actually correct the whole time. The meter was measuring the correct flows, but the reservoir was not depleting as the crack in the line was allowing for a large portion of the water to leak back into the reservoir. This was acting like a large unnecessary recycle line.
We are always willing to work with our customers to find real solutions to their challenges. In this case, we worked through the issue and solved the problem that was not obvious at the start. Sometimes the solution is technology related, but sometimes the simple answer is the key.