Remote Technologies RPC-320 manual Measuring Higher Voltages, Data logging on a timer tick

ANALOG INPUT

The outpu t voltage fro m the tem peratur e sensor is doubled by jumpering H1[5-7]. While this does not change the range the unit operates at, it does change increase temperature m easurement sensitivity.

Data logging on a timer tick

Some applications require that data is read at fixed intervals. The O NTI CK con struct is used to take data in intervals from 0. 01 to 327 seconds. The exam ple below takes 1 sample per second until 100 samples have been obtained.

10 DIM A(100)

20 ONTICK 1,500

30 REM THE REST OF YOUR PROGRAM

40 REM CONTINUES

80 GOTO 30

500 A(N) = AIN(3)

510 N=N+1

520 IF N = 100 THEN ONTICK 0,500

530 RETI

MEASURING HIGHER VOLTAGES

Voltages higher than + 5V are measur ed by inserting a series r esistor to the inp ut.

The table below shows resistor values for some input voltages using the 0-5V range.

Maximum

Input Voltage Resistor

620K

12.5150K

24380K

Use the following formula to determine the series resistance necessar y for a m aximum voltage input:

Rs =	Vi * 20000 - 100000	0 - 5V range
Rs =	Vi * 40000 - 100000	0 - 2.5V r ange

Rs is the re sistor value in ohms in ser ies with the inpu t. Vi is the maximum input voltage. W hen Rs is negative or zero, a series resistor is not necessary.

A high Rs v alue can ca use noisy r eadings. This is because the resistor acts as an antenna. To reduce noise, place a 0.1 mfd to 1 mfd capacitor betw een the input terminal and ground.

NOTE: When an input voltage exceeds the input range, other channel values are affected.

SECTION 10

Page 10-5 RPC -320