Campbell Scientific CR23X Micrologger - Manual (Page 135)

9-1
SECTION 9. INPUT/OUTPUT INSTRUCTIONS
TABLE 9-1. Input Voltage Ranges and Codes
Resolution
Range Codes* Full Scale Range Differential**
Fast
250
µ
s 60 Hz 50 Hz
Integ. Reject. Reject.
10 20 30 Autorange***
11 21 31 ± 10 mV 0.33 µV
12 22 32 ±50 mV 1.67 µV
13 23 33 ±200 mV 6.66 µV
14 24 34 ±1000 mV 33.3 µV
15 25 35 ±5000 mV 166 µV
* See “Measurements” section for a full list and explanation of possible range codes.
** Differential measurement, resolution for single-ended measurement is twice value shown.
*** See autoranging precaution in Table 3.5-1.
NOTE: When a voltage input exceeds the range programmed, the value which is stored is set to the
maximum negative number and displayed as -99999 in high resolution or -6999 in low resolution.
*** 1 SINGLE-ENDED VOLTS ***
FUNCTION
This Instruction is used to measure voltage at a
single-ended input with respect to ground.
Output is in millivolts.
PARAM. DATA
NUMBER TYPE DESCRIPTION
01: 2 Repetitions
02: 2 Range code (Table 9-1)
03: 2 Single-ended channel
number for first
measurement
04: 4 Input location for first
measurement
05: FP Multiplier
06: FP Offset
Input locations altered: 1 per repetition
*** 2 DIFFERENTIAL VOLTS ***
FUNCTION
This Instruction reads the voltage difference
between the high and low inputs of a differential
channel. Table 9-1 contains all valid voltage
ranges and their codes. Both the high and low
inputs must be within ± 5.0 V of the CR23X's
ground (see Common Mode Range in Section
14.7.2). Pyranometer and thermopile sensors
require a jumper between L and
to keep
them in Common Mode Range. Output is in
millivolts.
PARAM. DATA
NUMBER TYPE DESCRIPTION
01: 2 Repetitions
02: 2 Range code (Table 9-1)
03: 2 Differential channel
number for first
measurement
04: 4 Input location for first
measurement
05: FP Multiplier
06: FP Offset
Input locations altered: 1 per repetition
*** 3 PULSE COUNT ***
P3 Pulse Count is used to measure high
frequency and switch closure inputs on input
channels P1..P4 and C5..C8. Low level AC
inputs can also be measured on P1..P4. Table
9-2 shows how to select measurement options
discussed in this segment.