3M 747 ユーザーズマニュアル

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2.2 Threshold Resistance Settings for the 3M
 Shoes and Wrist Strap Tester 747
The test results indicated by the front panel LEDs are determined by comparison 
of the measured value with the threshold resistance settings (upper and lower 
limits).
LOW:   the measured resistance is below the lower 
threshold
OK:    the measured resistance is between the lower and 
upper thresholds
HIGH:  the measured resistance is above the upper 
threshold 
1.  ESD Shoe Test Threshold Resistance Settings 
The upper threshold (SHOES HIGH) and lower threshold (SHOES LOW) 
can be selected for shoe testing. Use tweezers to move the threshold switches
 
The upper threshold (SHOES HIGH) selections are 10, 35 or 100 
Ω. 
The lower threshold (SHOES LOW) selections are 100 k
Ω or 1 Ω.
2.  ESD Wrist Strap Test Threshold Resistance Settings 
The upper threshold (WRIST HIGH) can be selected for wrist strap testing. 
Use tweezers to move the threshold switch. 
The lower threshold is fixed at 1.65 
Ω for wrist strap testing. 
The upper threshold (WRIST HIGH) selections are 5, 10 or 35 M
Ω.
Important Notes:
•  Factory default settings are 100 M
Ω for SHOES HIGH, and 10 MΩ for WRIST HIGH, and 1 MΩ 
for SHOES LOW.
•  The SIGNAL OUT selection is set to SHOES. When operated as a stand-alone tester (that is, 
when not using the external output), this SIGNAL OUT selection should be set to either WRIST or 
SHOES.