NovaLynx Corporation
255-620-A Page 5 October 2022
4 PROGRAMMING
The ideal depth of water in an evaporation pan, for consistency, is between 2 and 3 inches below the
rim (i.e. 7" to 8" deep). Experiments have shown that the height of the rim of the pan above the water
surface affects the rate of evaporation. In order that the records from all stations will be comparable,
the pan should be filled to a level 2 inches below the rim, and refilled when the water has receded 1
inch (3 inches below the rim).
The automatic refill system operates close to this ideal, but some variance will occur due to mechanical
limits, water pressure variations, and differing rates of evaporation. The timer unit must be
programmed to suit the average of the environment where the evaporation pan will be used. Under
conditions of moderate rates of evaporation (~0.14"/day), the refill cycle can be set to repeat once a
week. Where evaporation is more rapid, the cycle may need to occur more frequently. If the average
rate of evaporation is known, one can approximately calculate how long it will take for the level to
drop an inch in the pan, and set the refill timer accordingly.
Instructions for setting and maintaining the timer is attached as an Appendix. Please set the following
parameters:
EXAMPLE
1. Current Time Set local time (using military time) HH:MM
2. Program 1
1st Opening Set a start time 07:00
1st Closing Set the stop time (= start + 10 minutes) 07:10
Note: Increase the stop time if needed for low pressure systems.
3. Program 2 Do not enable program 2
4. Weekly Program Select a day of the week Day 1
5 OPERATING CYCLE EXAMPLE
1. At the programmed time (7:00 am), the timer will open its valve and water will begin to fill the pan.
2. When the pan fills to about 9 inches deep, the float valve will stop the flow of water.
3. After 10 minutes (7:10 am) the timer will close its valve to stop the cycle.
4. One week later the cycle will repeat.
NOTE: The 255-200 Class A Evaporation Pan is 10 inches deep. When the automatic refill system is
installed on the rim of the pan and the water turned on, the pan will fill to a depth of 8.5 to 9.5
inches, depending on the water pressure. An inch of water is approximately 8 gallons.
