User manual

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
Ta bl e 2- 10 and Table 2-11are true for a CT ratio of 1:2500 and a burden
resistance of 31.5(Ω).