71M6403
Electronic Trip Unit
SEPTEMBER 2006
CE Calculations
The CE performs the precision computations necessary to accurately measure and detect current. The compute engine
firmware implements the following:
1. Supports 6 current sensing channels
2. Each channel individually configurable for Current Transformer or Rogowski coil
3. Each channel individually configurable for x8 gain for low signal sensors (MAX out < 20 mV)
4. Channel I4 configurable for Ground Fault current with fundamental frequency band pass filter or the vectorial sum of
first current input channel data (Insqsum)
5. Channel I5 includes a band pass filter to process the components of fundamental frequency of operation only
6. Programmable accumulation interval generates interrupt on DIO6 for data collection
7. Programmable FAULT_THRESH register sets over current detection to generate FAULT_PULSE on DIO7
8. Individual channel calibration coefficients to adjust the gain for desired accuracy
CE RAM Locations
CE Front End Data (Raw Data)
Access to the raw data provided by the AFE is possible by reading addresses 0 through 7, as listed below. The table also shows
the Configuration Register location for each input channel.
Input
Configuration
Register
Address (HEX)
Description
Channel
0x00
0x01
0x02
0x03
0x04
0x05
0x06
I0
I1
I2
I3
I4
0x28
0x29
0x2A
0x2B
0x2C
0x2D
--
Current input 0
Current input 1
Current input 2
Current input 3
Current input 4
Current input 5
Temperature
I5
TEMP
INEUTRAL monitor/compara-
tor input to power fault block
0x07
INEUTRAL
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© 2006 TERIDIAN Semiconductor Corporation
REV 1.0
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
