GE-IC693ALG221-Analog Current Input - 4 Channel

GE-IC693ALG221-Analog Current Input - 4 Channel

Conversion speed for each of the four channels is one-half millisecond. This provides an update rate of two milliseconds for any channel. Resolution of the converted signal is 12 bits binary (1 part in 4096) over either range. User data in the %AI registers is in 16-bit 2’s complement format. The placement of the 12 bits from the A/D converter in the %AI data word is shown below. The relationship between the current input and the data from the A/D converter is shown in Figures 3-14 and 3-15

If the current source is reversed into the input, or is less than the low end of the current range, then the module will output a data word corresponding to the low end of the current range (0000H in %AI). If an input that is out of range is entered (that is, it is greater than 20 mA), the A/D converter will output up to full scale (corresponding to 7FF8H in %AI). Input scaling is shown in the next figure

IC693ALG221 Analog Input Module Field Wiring Information The following figure provides information for connecting field wiring to the user terminal board on the 4-Channel Analog Current Input Module. TERMINALS FIELD WIRING 1 3 5 7 9 11 13 15 17 19 4 8 10 14 16 18 20 12 2 6 a44560 * 0–20MA CH1/2 * 0–20MA CH3/4 COM GND * COM GND * COM GND * COM GND * * OPTIONAL CONNECTIONS ( + ) ( – ) ( + ) ( – ) ( + ) ( – ) ( + ) ( – ) FIELD WIRING CH1 CH2 CH3 CH4 * * * * Figure 10-8. Field Wiring for 4 Channel Analog Current Input Module Note In order to limit common-mode voltages, each current source common line may also be tied to its associated COM terminal if the source is floating. These optional connections are shown in the figure above. Please refer to Chapter 2 for wiring and shield ground connection details.