Campbell Scientific CR510 Basic Datalogger - Manual (Page 105)

9-1
SECTION 9. INPUT/OUTPUT INSTRUCTIONS
TABLE 9-1. Input Voltage Ranges and Codes
Range Code
Slow
Fast
2.72ms 250µs 60 Hz 50 Hz
Integ. Integ. Reject Reject Full Scale Range Resolution*
1 11 21 31 ±2.5mV 0.33 µV
2 12 22 32 ±7.5mV 1. µV
3 13 23 33 ±25 mV 3.33 µV
4 14 24 34 ±250 mV 33.3 µV
5 15 25 35 ± 2500 mV 333. µV
* 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 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
*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
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 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
*** 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