Parameter Generation and Control 9354-4250, Installation And Operation Manual

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PGC, Inc. Appendix B; SmartPad version 0.503 Steady State & Programmable
November 2005 B-24
SET POINT ENTRY
(Programmable Mode)
The following sample program covers many of the different types of segments typically used.
NOTE - Although segment 00 is functionally equivalent to the other segments, it should
generally be avoided as the first segment in the program. Experience has shown that this
segment is the most common segment to be changed inadvertently.
It is advisable to sketch out the program before attempting to enter the data into the SmartPad™.
Sketching out the program serves several purposes; it helps to visualize the program, makes
entering the data easier, and provides a record for future reference.
Programs consist of
ramps and dwells , where a ramp is the time required for the set point to
reach the desired value, and a dwell is the time that the set point will remain at that value. If you
write your program with two different dwells immediately following each other, you will end up
with a dwell and a ramp.
Note: There is no "
ENTER " key; a field must be completely filled by entering numerals from
the Number Pad.
WRITING THE PROGRAM ON PAPER
In this sample program it is assumed that slow damper cascade control mode is selected. If two-
temperature control mode is selected H2O set point will be entered instead of % RH set point.
Example : From the water spray/RH graph supplied with this unit, follow the desired dry bulb
temperature (vertical lines) and Relative Humidity (horizontal lines). The intersection of these
two lines defines the water spray temperature (curved lines) necessary to achieve the desired
conditions.
SEGMENT 01:
1.) Time set in hours, minutes and seconds is the time to proceed to the conditions desired. IMPORTANT
- Since the starting point of the SmartPad™ is unknown, program the time in the first segment of the
program for a short interval, such as one second, to bring the SmartPad™ to a known starting value.
2.) Select the dry-bulb temperature at which the test is to start. Enter this temperature to 1/10 degree
Centigrade on the programming sheet. For this example; 25 degrees Centigrade = 25.0.
3.) Select the desired Relative Humidity. Example: 45% RH.
SEGMENT 02: Program the same conditions as segment 01 with the time at 30 minutes. This will allow time for
the conditioner to stabilize at 25.0°C and 45% RH.
SEGMENT 03: For the next condition in the test, we wish to hold the same dry-bulb temperature but raise the
humidity from 45% to 55% in a controlled ramp. Allow 45 minutes for the unit to ramp the RH from 45% to 55%.
SEGMENT 04: We now wish to hold this condition for thirty minutes.
SEGMENT 05 : The next condition desired is to raise the air temperature to 35 deg. C with a relative humidity of
60.5%. We will allow one hour and twenty minutes for this controlled ramp of both the air and RH to these new
conditions.
SEGMENT 06: If desired, we may hold these conditions for a maximum of to 17 hours 59 minutes and 59
seconds. If a longer time is required two steps must be used. We will select 15 minutes.