Microchip Technology ADM00333 Benutzerhandbuch

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PIC18F87J72 Evaluation Board User’s Guide
DS51990A-page 16
© 2011 Microchip Technology Inc.
TABLE 2-11:
JUMPER SETTINGS FOR CURRENT MEASUREMENT ON CH1
CH1 Jumper Position
ADC 
Remark
CT Primary 
Current 
(Irms-A)
JP1
JP2
JP3
JP4
ADC I/P 
(Vrms)
ADC I/P 
(Vpeak)
0.1
Short 2-3
Open
Short
Open
0.00063
0.00089
Internal Gain of 2 can be used for 
better resolution
0.5
Short 2-3
Open
Short
Open
0.00315
0.00445
1
Short 2-3
Open
Short
Open
0.0063
0.00891
10
Short 2-3
Open
Short
Open
0.063
0.08910
20
Short 2-3
Open
Short
Open
0.126
0.17819
30
Short 2-3
Open
Short
Open
0.189
0.26729
Max Differential ADC I/P is 0.5V
Note 1:
The precautions given need to be strictly adhered to, in order to avoid any damage to the evaluation board 
and prevent electric shock hazard.
2:
I/P CT Secondary is connected between pins 1 and 3 of J4 and J5.
3:
The resistors R26, R27, R28 and R29 need to be populated. These resistors act as burden resistors for 
CT secondary.
4:
The calculations given in 
 and 
are true for a CT ratio of 1:2500 and a burden 
resistance of 31.5(Ω).