B&B Electronics 232OPSDA manual A/D Connections

Chapter 2: Connections

This chapter will cover the connections required for the 232OPSDA. Four sets of connections are required: A/D converter, digital I/O, serial port, and power supply connections. Do not make any connections until you have read this chapter. If you do not use a particular type of connection, it is still important to read each section. Table 2.1 shows the terminal block assignments.

Table 2.1: Terminal Block Assignments

Terminal	Function	Description
Block
TB 0	A/D 0	4-20mA Current Loop Input Channel*
TB 1	A/D 1	Buffered 0 to 5V A/D Channel**
TB 2	A/D 2	Buffered 0 to 5V A/D Channel
TB 3	A/D 3	0 to 10V A/D Channel
TB 4	A/D 4	Non-buffered 0 to 5V A/D Channel
TB 5	A/D 5	Non-buffered 0 to 5V A/D Channel
TB 6	Digital out	Digital Output
TB 7	Digital in	Digital Input
GND	GND	Ground
+12VDC	+12VDC	Power Supply Connection

*The current loop input uses a non-inverting amplifier that has a gain of 23.064. Space for through-hole resistors is provided to change the gain. By decreasing the gain, currents up to 100mA can be read with A/D 0.

**This A/D input uses a voltage follower circuit. Spaces for through- hole resistors are provided to convert the voltage follower into a non- inverting amplifier with gain > 1.

A/D Connections

The A/D connections are made on the I/O port which consists of ten terminal blocks. Terminal Blocks 0-5 are A/D channels 0-5. These six A/D channels are referenced to GND (terminal block 8). The 4-20mA Current Loop A/D channel requires connections different from the other five channels, so two different diagrams are shown for required A/D connections. Figure 2.1 shows the connections required for the 4-20mA Current Loop channel (A/D 0), and Figure 2.2 shows the connections required for A/D channels 1- 5.

Documentation Number 232OPSDA1397 Manual 5

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