Part 2: Sorry had to run and take care of another issue. As for the other questions. The TDS meter samples water from the cooling tower. This is the meter that is affected. The reading is normally stable and increases as water evaporates from the cooling tower. From the calibration point the meter usually rises at a steady rate changing by a factor of 10 over a period of about 30 minutes. When the fans and drives are ramping up and down, it can change by a factor of 300 in the same time frame. At a pre-set conductivity level, the meter trips a valve which allows water to escape from the towers and fresh water is added to lower the amount of dissolved solids and there-by the conductivity of the water. What has been happening is, that when the tower fans ramp up to maintain the temperature the conductivity reading starts to fall and vice versa. As long as the fan speed is stable, so is the indicated conductivity. There seems to be a time delay factor with the reading chasing the fan speed at about a 45 second interval. We moved the meter out of the tower yard and put it in the chiller mechanical room inside the building. When water is supplied to the meter from downstream from the chillers the meter tracks normally, powered from any source, including power from the tower yard. When water is supplied from the tower yard or anyplace up to where it enters the chillers, the meter operates erratically. It appears that the steel chiller barrels and the copper tubing is somehow damping down the noise to a point where the meter can operate. Any attempt to date to ground the towers, motors, conduit, water pipe and anything else we could think of has proven to be ineffective. Until I can find a way to get money for a signal analyzer test authorized, I don’t know exactly what I’m chasing. We surmise that the drives are the root of the problem, but why now after 6 years? Without knowing the nature of the noise, you can’t choose a filter to do the job. We are trying to figure out a way of taking the noise out of the water at the tower as a means of fighting a holding battle until we can identify exactly what we are dealing with. How much surface area will be needed to capture the noise? Will taking it to earth ground in the tower yard work if we attach it to the lighting arrestor system? Any and All suggestions are welcome.
