ITT Industries PumpSmart PS200, Configuration & Operation Manual

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PS200 Configuration & Operation Guide
OPTIONS & FEATURES
Page 77
CALCULATING “K” VALUE
The general equation for calculating the “K” value of a differential pressure flowmeter is:
K = Q / P
0.5
Where:
Q is the flow corresponding to full-scale dP (20mA) in GPM or M3/Hr for the pumped liquid.
P is the full-scale differential pressure, in Ft or M, based on a specific gravity of 1.0. Refer to the manufacturers
literature or transmitter nameplate for these values.
NOTE – Units must correspond (i.e. Ft must be used with GPM. M must be used with M3/Hr). Conversion is
required even if parameters 16.03 or 16.06 are set to PSI or BAR. Common conversions:
Ft = PSI x 2.31
M = BAR x 10.2114
NOTE(s)
The PumpSmart software uses only one “K” constant, therefore; if two DP flowmeters are used (17.01 and 17.02
are both quadratic) both flowmeters must have the same K value setting.
Differential pressure flowmeters are not suitable for services where the specific gravity of the fluid varies widely.
Use a direct reading type [e.g. Magnetic] flowmeter in these cases.
Example: In this example calculation, a 3” orifice plate flowmeter is being used with a differential pressure
transmitter. The orifice plate is rated for 16-225 GPM and the dP pressure transmitter is scaled for 0-2.58 Ft. The
Resulting “K” value would be:
K = 225/(2.58)
0.5
= 140.07
Note: The dP transmitter full scale value (20 mA) corresponds to a flow of 225 GPM.
Energy Savings Information
PumpSmart can calculate the energy savings as compared to a constant speed pump application. To enable this
function to perform properly, local energy costs and comparative application information must be entered.
Enter the local energy cost in $ (local currency) per kWh into parameter 26.01and then enter the nominal power
rating of a comparable fixed speed unit into parameter 26.02. To find this, look at the pump performance curve
and enter the power for the rated operating point.
Example - If your power cost is $0.06 per kWh, enter a value of .06 into parameter 26.01.
Parameter Name Value/Range Note(s)
26.01 $/kWh 0-1.00
0
[default]
26.02 BASELINE POWER 0-1000 Hp
0
[default]
26.05 ENERGY SAVE RESET DISABLED [
[default]
RESET
Allows resetting of savings to zero.
One of the benefits of using PumpSmart is its ability to automatically shut off the pump when not required.
Parameter 26.04 SAVINGS OPTION #2 allows the savings of using PumpSmart to be tracked during automatic
shutdown.