CCS LCDA-P Installation and operating instructions

LCDA-P Power Display 1
Continental Control Systems LLC
Application Note: AN-116
July 2008
LCDA-P Power Display
Overview
The power display has eight digits with an adjustable scale factor and decimal point posi-
tion, to allow for the accurate display of power levels from tenths of a watt to megawatts.
The power display is self-powered for use with the Advanced Pulse WattNode models with
an output frequency up to 20Hz. For Advanced Pulse WattNode models with an output fre-
quency greater than 20Hz an external DC power supply and pull-up resistor are required.
Wiring
Low Pulse Frequency (up to 20Hz)
Connect the WattNode’s ‘P1’ terminal of the output to the IN B (Terminal 2) on the LCD
display. Connect the WattNode’s ‘COM’ terminal of the output to the GND (Terminal 1) on
the LCD display.
P1
P2
P3
COM
A CT
O
/
B CT
O
/
C CT
O
/
tuptuO
B
O
/
C
O
/
Status
Status
Status
WATT N ODE ®
WNB-3Y-208-P
N
A
O
/
5 Enable/R
RST 4
IN A 3
IN B 2
GND 1
6 DC Common
7 +10-30VDC
LCDA-P Low Pulse Frequency Wiring DiagramFigure 1:
High Pulse Frequency (greater than 20Hz)
Connect the WattNode’s ‘P1’ terminal of the output to the IN A (Terminal 3) on the LCD
display. Connect the WattNode’s ‘COM’ terminal of the output to the GND (Terminal 1) on
the LCD display. Add a pull-up resistor on the P1 line as shown below. See Table 1 below
for recommended pull-up resistor values.
P1
P2
P3
COM
A CT
O
/
B CT
O
/
C CT
O
/
tuptuO
B
O
/
C
O
/
Status
Status
Status
WATT N ODE ®
WNB-3Y-208-P
N
A
O
/
5 Enable/R
RST 4
IN A 3
IN B 2
GND 1
6 DC Common
7 +10-30VDC
+5V to +28Vdc
Resistor values
See Table 1
LCDA-P High Pulse Frequency Wiring DiagramFigure 2:

LCDA-P Power Display 2
Continental Control Systems, LLC AN-116
Full-Scale
Pulse
Frequency
Pull-up to 5.0V
Recd (Min-Max) Pull-up to 12V Recd (Min-Max) Pull-up to 24V Recd (Min-Max)
20 Hz 20kΩ (1.0k-300k) 47kΩ (2.4k-470k) 100kΩ (4.7k-540k)
50 Hz 10kΩ (1.0k-130k) 20kΩ (2.4k-200k) 47kΩ (4.7k-270k)
100 Hz 4.7kΩ (1.0k-62k) 10kΩ (2.4k-100k) 20kΩ (4.7k-130k)
200 Hz 2.0kΩ (1.0k-33k) 4.7kΩ (2.4k-47k) 10kΩ (4.7k-68k)
600 Hz 2.0kΩ (1.0k-12k) 4.7kΩ (2.4k-16k) 10kΩ (4.7k-22k)
Recommended Pull-up ResistorsTable 1:
Programming the Power Display
The LCDA-P is shipped pre-programmed if ordered with an Advanced Pulse WattNode
and current transformers. To make changes to the original program, follow the steps below.
Refer to the Durant Ratemeter Installation manual for details on programming the scale
factors and installing the LCD display.
For the power display, the LCD will display the input pulse frequency times the scale factor.
1) The decimal point is then superimposed on the resulting number. Start by selecting the
WattNode model from the table below.
Model Number of CTs Vc
WNB-3Y-208 -P 1, 2, or 3 120
WNB-3Y-400-P 1, 2, or 3 230
WNB-3Y-480-P 1, 2, or 3 277
WNB-3Y- 600-P 1, 2, or 3 347
WNB-3D-240-P 1, 2, or 3 120
WNB-3D-400-P 1, 2, or 3 230
WNB-3D-480-P 1, 2, or 3 277
Compute maximum measured power:
2) Pm(watts) = Vc · CTAmps · NumOfCTs
Where Vc comes from the above table, CTAmps is the rated current of the current trans-
formers being used, and NumOfCTs is the number of CTs being used with the WattNode.
The WattNode can measure power levels up to 50% over the rated limits, so you may want
to increase Pm by up to 50% if you wish to allow some overhead. If the WattNode outputs
a power greater than the display can handle, then the display will show ‘----‘.

LCDA-P Power Display 3
Continental Control Systems, LLC AN-116
© 2008 Continental Control Systems 3131 Indian Rd., Suite A
http://www.ccontrolsys.com Boulder, CO 80301
WattNode is a registered trademark of Continental Control Systems, LLC Phone: [phone]
This document is subject to change without notice. FAX: [phone]
Choose a row from the following table so that3) Pm is less than Expected Maximum Power
with the Desired Display Format.
Expected
Maximum
Power
Desired
Display
Format1
Display
Resolution Scale Factor Equation (20Hz Output)2Rate Multiplier
999.9 W 000.0 W 0.1 W Vc • CTAmps • 3 / 2 1
9999 W 0000 W 1 W Vc • CTAmps • 3 / 20 1
9.999 kW 0.000 kW 1 W (0.001 kW) Vc • CTAmps • 3 / 20 1
99990 W 00000 W 10 W Vc • CTAmps • 3 / 200 10
99.99 kW 00.00 kW 10 W (0.01 kW) Vc • CTAmps • 3 / 200 1
999.9 kW 000.0 kW 100 W (0.1 kW) Vc • CTAmps • 3 / 2000 1
9999 kW 0000 kW 1 kW Vc • CTAmps • 3 / 20000 1
9.999 MW 0.000 MW 1 kW (0.001 MW) Vc • CTAmps • 3 / 20000 1
1W, kW, or MW will not appear on the LCD display.
2The scale factors are valid only with a WattNode with a 20Hz full-scale pulse frequency.
Compute the scale factor. On program mode screen 1 enter your computed scale factor.
4) Example: if your computed scale factor is 12.4137, round to 12.41, enter the four digits
1241, and then move the decimal point so that 12.41 is displayed.
On program mode screen 2 adjust the decimal point location to match the Desired Display5) Format.
On program mode screen 3 set the Rate Multiplier to 1 or 10 as shown in the table above.
6)