Service manual

RC2000 Service Manual Chapter 6 Using the RS232-RS422 Protocol Converter 36
Research Concepts, Inc; 10679 Widmer; Lenexa, Kansas; USA 66215 WWW.RESEARCHCONCEPTS.COM
6.3 Alternate Test Procedure for the RC1KADP
6.3.1 Test Procedure for RS485A1 Board (RC1KADP)
1. Clip lead TX1 to RX1 on terminal output strip
2. Clip lead TX2 to RX2 on terminal output strip.
3. Connect ground lead to power supply ground and voltmeter ground, then apply to pin
on input terminal strip.
4. Apply 9V/200mA to J3 jack.
5. Monitor terminal TXD on J1 with red lead from voltmeter while applying and releasing
6-8VDC to terminal RXD on J1. Applying 6-8VDC to RXC should cause roughly a
9VDC level on TXD; removing the voltage should result in a –9VDC reading.