Campbell Scientific SDM-INT8 8-Channel Interval Timer User Manual
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SDM-INT8 8 Channel Interval Timer
*Table 1 Programs
01: 1
Sec.
Execution
interval
1: SDM-INT8 (P101)
measure wind speed
1: 00
Address
Option
2: 0022
Chan8765=HLrise/HLrise/LLrise/LLrise/
3: 2222
Chan4321=LLrise/LLrise/LLrise/LLrise
4: 0022
Chan8765=none/none/kHz/kHz/
5: 2222
Chan4321=kHz/kHz/kHz/kHz/
6: 0
Execution interval averaging (1 second)
7: 1
Loc [:m/s ]
8: 98.0
Mult m/s (convert from kHz to m/s)
9: 0
Offset
2: Excite,Delay,Volt(SE) (P4)
measure wind direction
1: 6
Reps
2: 15
2500 mV fast Range
3: 1
IN
Chan
4: 1
Excite all reps w/EXchan 1
5: 0
Delay
(units
.01sec)
6: 2500
mV
Excitation
7: 7
Loc [:degrees ]
8: .1420
Mult
degrees
9: 0
Offset
7.2.3 Brake Pressure and Wheel Speed Test - Capture All Events and P23
Burst Mode
A CR10X controls an INT8 to capture about 2 seconds worth of wheel speeds
while measuring corresponding brake pressures in Burst Mode. The CR10X's
Burst Mode (P23) triggers the INT8 with Control Port 1 (C1) when the first
analog channel measures pressure over the trigger level.
Flag 1 is manually set by the operator to control when the program is entered.
After each test, the program sets Flag 1 low to return control to the operator.
The first time through the table, the INT8 is programmed and starts measuring,
looking for the edge on channel 1 that the Burst Mode Instruction (P23) will
trigger using C1.
The real time of the brake event (immediately after it occurred) is stored in
array ID 9 with P77, followed by the analog burst data in arrays 1,2,3,4 and the
timing data from the INT8 (picked up each time on the subsequent time
through the table) in arrays 5,6,7,8.
The Burst Mode measures for 2 seconds (200 scans at 10 ms/scan). The INT8
measures for about the same 2 seconds, as defined by the trigger edge on
channel 1 caused by the start of Burst Mode and the ending edge caused by
pulsing Port 1 after the Burst Mode. Data from the INT8 is stored in Final
Storage the next time the table is executed, and the INT8 is reinitialized for the
next brake event.
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