Loop Detector: GVD 

Positive(24VDC), Fire Line(220VAC)
Negative(24VDC), Zero Line(220VAC)
Pulse relay, Normal open connection
Pulse relaly, Common connection
Existence relay, Normal open connection
Existence relay, Common connection
Loop

Power ground wire(220VAC)
Existence relay, Normal close connection
Pulse relay, Normal close connection
Power requirements: 24 VDC(GVD221, GVD222); 220VAC(GVD201, GVD202)
Frequency Tuning: Fully automatic
Iuductance Value: 20-1500uH
Sensitivity: Eight grade
Working Frequency: 2 switches Alternative, Frequency depends mainly on coil geometry, The frequency: 20-200kHz
Automatic Sensitivity upgrade: Switches alternative
Pulse relay working mode: Leave pulse/Enter pulse
Response time: 100ms
Drift Compensation Rate: Timely compensation
Working Temperature: -40C--80C

Double Channels
Positive(24VDC), Fire Line(220VAC)
Negative(24VDC), Zero Line(220VAC)
Channel 1Loop
Channel 2 Loop
Channel 2 Relay, normal open connections
Channel 2 Relay, common connections
Power ground wire(220VAC)
Channel 1 Relay, normal open connections
Channel 1 Relay, common connections
Power requirements: 24 VDC(GVD221, GVD222); 220VAC(GVD201, GVD202)
Frequency Tuning: Fully automatic
Iuductance Value: 40-2000uH
Sensitivity: Panels on the Grade 4 scale
Working Frequency: 2 switches Alternative, Frequency depends mainly on coil geometry, The frequency: 20-200kHz
Automatic Sensitivity upgrade: Switches alternative
Pulse relay working mode: Leave pulse/Enter pulse
Response time: 200ms
Drift Compensation Rate: Timely compensation
Working Temperature: -40C--80C
 

Warranty time: 1 year for digital parts.