WPI EVOM3, Инструкция по эксплуатации

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EVOM3
World Precision Instruments 35
*Drift–Readings that continuously increase or decreases a significant value (either
voltage or resistance) over time. Example 1: At 10 mV the PD reading is increasing
1 mV/minute. (A drift of 0.1 mV/minute is acceptable.) Example 2: At 1000 Ω the
reading is increasing 100 Ω/minute. (A drift of 10 Ω/minute is acceptable.) Excessive
drift may be caused by a coated electrode, pH or temperature changes. See the
Troubleshooting entry on drifting above. Also see "Instrument Diagnostics and
Calibration" on page 21 or "Testing the STX2-PLUS Electrodes" on page 28.
Instability–At 500 Ω, the reading jumps from 450 to 550 Ω and will not settle down (an
instability ±5 Ω is acceptable in the 500 Ω range. In the higher ranges, up to ±1000 Ω is
acceptable at the 100K range. Electrodes showing instability may be coated with DMEM
and require enzymatic cleaning. See "Cleaning/Maintaining the STX2-PLUS Electrodes" on
page 26.
SPECIFICATIONS
This unit conforms to the following specifications:
Tissue Sampling Frequency ................................................................................................12.5 Hz
Sample Averaging .......................................................................... 20 samples running average
Resistance Ranges ..................................................................................................... 0 to 10,000 Ω
........................................................................................................................................ 0 to 50,000 Ω
.............................................................................................................................0 to 100,000 Ω +5%
Auto Mode ....................................................1 to 100,000 Ω auto current 2 μA, 4 μA, 10 μA
Resistance Resolution ................................................ 0.1 Ω (under 200 Ω); 1 Ω (over 200 Ω)
Resistance Accuracy ........................................... 0.1 Ω (under 200 Ω), 1 Ω (over 200 Ω) 0.1%
.......................................................................................................... 100,000 Ω ± 2 μA (to 105 KΩ)
Voltage Resolution..................................................................................................0.001 V, 0.1 mV
Accuracy Resistance ...............................................................0.1 Ω (200 Ω); 1 Ω (above 200 Ω)
Accuracy voltage ..................................................................................................................± 0.1 mV
Current Levels ...................................................................................................... 10,000 Ω ±10 µA
........................................................................................................50,000 Ω ± 4 µA
..................................................................................................... 100,000 Ω ± 2 µA
............................................. Auto mode 1 to 100,000 Ω auto current 2 µA, 4
Display Update Rate .....................................................................................................0.5 seconds
Battery ....................................................................................................... 3.7V Li-ion 2500 mAh**
Charging Period ........................................................5.5 hours (power off); 8 hours (run time)
Charge Current .....................................................................................................................200 mA
Power Consumption ......................................................................................................... ~250 mA
Certifications .................................................................................................................................... CE
Firmware ..................................................................................................................... Upgradeable*
* NOTE : A USB to Mini-B cable (WPI # 803026 ) is required along with PC bootloader
software and the image are required to upgrade the firmware.
**Not user serviceable. Contact WPI for repair or replacement.