GD-77KDG Detector Head

Features

• Digital display with LCD back light
• Sensor information and calibration is stored within sensor memory
• Self-diagnostic functions by microprocessor
• Electrochemical sensors for most semiconductor gases
• Built-in sampling pump
• Easy replacement of pump and sensor
• Two alarm levels
• 24VDC operation

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Applications

• Semiconductor
• Chemical Processing
• Laboratory
• Manufacturing

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The Model GD-K77DG and GD-K77DG-NT use pyrolysis to oxidize NF, (Nitrogen triflouride); which is then detected as NO2 with an electrochemical sensor. The Model GD-S77DG and S77DG-NT also use pyrolysis to oxidize TEOS (Tetraethoxysilane). The resulting SiO2 (Silicon dioxide) is then detected in a ionization chamber. This advanced method offers distinct advantages compared to conventional TEOS detection (Hydrolysis/electrochemical sensor): long sensor life and virtually no interference from other gases.

Detection principle	Pyrolysis/electrochemical cell
Detection method	Sample drawing type
Detectable gas and measuring range	NF, 0-30ppm
Signal transmission	Analog transmission (4-20 mA)
Display	Digital LED display of gas concentration, 4 digits
Gas alarms	Two alarm levels: 1st alarm (Yellow LED), 2nd alarm (Red LED)
Dry outputs for remote alarms	Dry contact relay for 1st, 2nd, and trouble alarms (Normally Open or Normally Closed)
Alarm delay time	Approximately 30 seconds when exposed to gas concentration of 1.6 times alarm level (Same as T60)
Self diagnosistic function	Trouble, low flow, system failure, communication error
Operating conditions	0 - 40•C, 30 - 85% R.H.
Power requirements	24 VDC ± 10%, Approx. 10W and 100 ~ 120VAC or 220 ~ 240VAC
Applicable cable	Shielded cable 3C, 1.25 sq (18 gauge)
Enclosure	Wall mounting, Munsel No. 2.5Y9/2 (Beige)
Dimensions	5.6" (W) x 6.7" (H) x 6.0" (D), approximately 7.0 lbs 140 mm (W) x 170 mm (H) x 153 mm (D), approximately 3.2 kg

Partial List Of Detectable Gases
Many other gases or ranges available.

Ammonia (NH3)	0 - 75.0 ppm
Arsine (AsH3 )	0 - 0.20 ppm
Boron Trichloride (BCl3)	0 - 15.0 ppm
Chlorine (Cl2)	0 - 3.0 ppm
Chlorine Trifluoride (ClF3)	0 - 0.6 ppm
Combustibles	0 -100% LEL
Diborane (B2H6)	0 - 0.30 ppm
Fluorine (F2)	0 - 6.0 ppm
Hydrogen (H2)	0 - 2000 ppm
Hydrogen Chloride (HCl)	0 - 15.0 ppm
Hydrogen Fluoride (HF)	0 - 9.0 ppm
Hydrogen Sulfide (H2S)	0 -100.0 ppm
Nitrogen Dioxide (NO2)	0 - 15.0 ppm
Oxygen (O2)	0 - 25.0 %
Ozone (O3)	0 - 1.0 ppm
Phosphine (PH3)	0 - 1.0 ppm
Silane (SiH4)	0 - 15.0 ppm