Campbell Scientific TDR100 Time Domain Reflectometry Systems - Manual (Page 8)

TDR100
2. System Specifications
2.1 General
See the CR10X, CR23X, CR800/CR850, CR1000, or CR3000 datalogger
manuals for datalogger specifications.
2.2 Power Consumption
2.2.1 TDR100
• The current demand for the TDR100 during measurement is 270
milliamps.
• When the TDR100 is controlled by a datalogger, a 35 second timer puts
the device in sleep mode requiring about 20 milliamps. After 35 seconds
in sleep mode, a timer puts the TDR100 in standby mode requiring about
2 milliamps.
• When the TDR100 is controlled by PCTDR, a 60 second time-out puts
the device in low power mode requiring about 60 milliamps.
2.2.2 SDMX50
• The quiescent current demand for the SDMX50 multiplexer is less than 1
milliamp.
• Current demand during switching is approximately 90 milliamps.
• All multiplexers of the same level switch simultaneously (see Figure 5-1).
Switching takes less than 1 second.
2.3 TDR100 Performance Specifications
pulse generator output 250 mV into 50 ohms
output impedance 50 ohms ± 1%
time response of combined pulse
generator and sampling circuit ≤ 300 picoseconds
pulse generator aberrations ±5% within first 10 nanoseconds
±0.5% after 10 nanoseconds
pulse length 14 microseconds
timing resolution 12.2 picoseconds
waveform sampling
range
resolution
20 to 2048 waveform values over
chosen length
distance (V
p
= 1) time (1 way travel)
-2 to 2100 meters 0 to 7 microseconds
1.8 millimeter 6.1 picoseconds
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