Input/Output Instructions - Campbell CR510 Operator's Manual

SECTION 9. INPUT/OUTPUT INSTRUCTIONS
Slow
2.72ms
Integ.
1
2
3
4
5
* Differential measurement; resolution for single-ended measurement is twice value shown.
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
01: 2
02: 2
03: 2
04: 4
05: FP
06: FP
Input locations altered: 1
*Repetitions for the input/output instructions are
limited to two differential or four single ended
measurements.
*** 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 ±2.5 V of the CR510's
ground (see Common Mode Range in Section
TABLE 9-1. Input Voltage Ranges and Codes
Range Code
Fast
250µs 60 Hz
Integ. Reject
11 21
12 22
13 23
14 24
15 25
DESCRIPTION
Repetitions*
Range code (Table 9-1)
Single-ended channel
number for first
measurement
input location for first
measurement
Multiplier
Offset
50 Hz
Reject Full Scale Range
31 ±2.5mV
32 ±7.5mV
33 ±25 mV
34 ±250 mV
35 ±2500 mV
14.7.2). Pyranometer and thermopile sensors
require a jumper between LO and GROUND to
keep them in Common Mode Range. Output is
in millivolts.
PARAM. DATA
NUMBER TYPE
01: 2
02: 2
03: 2
04: 4
05: FP
06: FP
Input locations altered: 1
*** 3 PULSE COUNT ***
There are three pulse input types which may be
measured with the Pulse Count Instruction. The
Pulse Count Instruction may also be used to
measure switch closures (<40 Hz ) with Control
Port C2 see Section 8.5 for examples).
HIGH FREQUENCY PULSE
In this configuration, the minimum detectable
pulse width is 2 microseconds, i.e. the
maximum frequency is 250 kHz with a 50% duty
cycle. The 8 bit counter has a maximum input
frequency of 2000 Hz and the 16 bit option a
maximum of 250 kHz. The count is incremented
when input voltage changes from below 1.5
Resolution*
0.33 µV
1. µV
3.33 µV
33.3 µV
333. µV
DESCRIPTION
Repetitions
Range code (Table 9-1)
Differential channel
number for first
measurement
Input location for first
measurement
Multiplier
Offset
9-1