Monroe-electronics 275A 接地测试系统

Indicators, LED: 
RED Hazard: Resistance below 500kΩ
GREEN Safe: Resistance between 500kΩ
and 10 MΩor 100MΩ(selectable)
YELLOW Open: Resistance above 10MΩor 100MΩ
(selectable)
Audible alarm: Sounds for Open or Hazard condition
Tolerance: +10% of value
Battery: 9 volt, Eveready 216 or NEDA #1604
alkaline
Size: 3.8” x 2.4” x 1.1”
Weight 4 oz
Accesories: Manual, connecting cable, 9V battery

DataSheet
The model 275A measures the resistance of personnel grounding systems (wrist straps and heel straps) and work area grounding systems (table mats and floor mats), and indicates if the resistance is high (open), low (hazard), or within acceptable limits to control damage to sensitive components due to electrostatic discharges.
Testing is as easy as pushing the test button and observing the color-coded indicator lights. The safe operating limit can be set at 10M or 100M ohms using a switch on the front of the instrument. The instrument is supplied with a ground cord. An optional leather carrying case is available.