DNF Controls DC20 - Manual (Page 22)

Flex Control Network ® , DC20 / DC21 User Manual Page 22
GPIO CONNECTORS: (DC21 Only)
GPI 1 – 16, GPI 17 – 32, GPO 1 – 16, GPO 17 - 32; 4 x 37-Pin Female (D37F)
GPI: Opto Isolated Input. GPI source must provide power to turn on
opto-isolator.
GPI Opto-isolator Input:
5V - 12 V input voltage
24V use external resistor = 680 - 820 ohm
20ma MAXIMUM CURRENT
Specification for GPI input:
1. Voltage: (Internal resistor only)
+3.3V minimum
+5V typical
+6V maximum
2. Current: (Internal resistor only)
5mA minimum
10mA typical
15mA maximum
For typical 10mA current, if external voltage is
higher than +5V, a series resistor is required:
R ext = (V ext - 4.5) / 0.01
V ext = +9V => R ext = 450 Ohms
V ext = +12V => R ext = 750 Ohms
V ext = +24V => R ext = 1950 Ohms
R
Internal
330 Ohms R
External
External
Device
Ground
Power