I accept information:
Specifications for GAO Position Markers (GAO 491013, GAO 491014):

• Compatibility: GAO 137001, 137003, 137004 Tags with Marker feature
• Frequency: 125KHz
• Modulation: AM
• Position data: 16bits (programmable)
• Loop current: Max 6App
• User Interface: Bus i-BUS (RS422); Manual Blue Tooth, Class 2, SPP Profile; Indicators 4 LEDs, Bicolor (Run, Loop, Bus, Error); Features Programming of Loop ID, Setting of loop current (range) Loop diagnosis
• Electrical: Supply voltage DC 10 to 30V / AC* 85 to 265V; Power consumption Max. 20W
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