• Self-tuning and complete environmental tracking
• Two selectable modes per channel:
Presence, normal hold time
Pulse
• Status output provides individual channel status states as defined by NEMA TS-2
• Front panel indicator also displays status states
• DIP switches on front panel for sensitivity, frequency, and mode selections
• Eight levels of sensitivity per channel
• Four loop frequencies per channel
• Two detector channels in a single unit
• Loops are sequentially scanned, which helps eliminate crosstalk
• Complete low power CMOS digital design
• Operates on a single DC power supply
• Transformer isolation for loops
• High intensity multipurpose red LED indicators
• Front panel width is 1.12" (2.84 cm)

Specifications

Self-Tuning: Operational within one second after application of power or after a reset command. 30 seconds of operation is required before full presence time is possible.

Environmental and Drift Tracking: Fully self-compensating for environmental changes and component drift over full temperature range and entire loop inductance range.

Loop Inductance Range: 50 - 1,000 Microhenries with Q factor of 5 or greater.

Loop Feeder Length: Up to 2,000 ft (600 m) maximum with proper feeder cable and appropriate loops.

Loop Input: Transformer isolated.

Loop Frequency: Four selectable frequencies (normally in the range of 20-70 kilohertz) are provided for each channel).

Grounded Loop Operation: The loop isolation transformer allows operation with poor quality loops, including a single point short-to-ground.

Lightning Protection: The detector can tolerate, without damage, a 10 microfarad capacitor charged to 2,000 volts to be discharged directly into the loop input terminals, or a 10 microfarad capacitor charged to 2,000 volts discharged between either loop terminal and earth ground.

External Reset: Switch closure between DC Common (pin A) and the reset line (pin C) for 15 microseconds or longer will reset both detector channels.

Manual Reset:

• Both channels of the detector may be manually reset by removing power momentarily.
• An individual channel may be manually reset by momentarily changing the sensitivity setting.

Sequential Scanning: The two loops are alternately turned ON and OFF to minimize crosstalk.

Response Time (Under Construction): Measured with same SENS level setting on both channels.

Output Conditions Table (Under Construction):

Sensitivity (Under Construction): Vehicle detection results from a sufficient negative change in loop inductance (-delta L/L). Note that the detector channel is reset automatically whenever the sensitivity level is changed.

Detect Indicator Operation: Hi intensity red light emitting diode (LED) indicates:

• Call output
• Status for each detector channel

Modes:

• PRES: Presence mode with a hold time of 4 minutes minimum (regardless of vehicle size) and typically 20 to 30 minutes for a car. (Other times are possible by special order from the factory.)
• PUL: In the pulse mode each vehicle generates a pulse output of 125 ± 25 milliseconds. Should a vehicle remain over the loop for 2 seconds or longer, the detector will tune out the vehicle such that the remainder of the loop zone detects subsequent vehicles after 2 seconds. When the vehicle leaves the loop, the detector resumes full sensitivity within 0.75 seconds. Option: Pulse 250 ms.
• STATUS: Not truly a mode, this function permits the CALL indicator to display the last fault recorded in memory since last reset or power up. If no failure has occurred, indicator and output shall be in Condition 1. See power up for indicator display and output conditions.

Call Output Circuit Rating: Optically coupled transistors; 40 VDC maximum collector to emitter; 50 milliamps maximum collector current. The transistor saturation level is 1.2 VDC maximum. The output transistor is protected with a 47 volt zener diode connected across the emitter and collector.

Status Output Circuit Rating: An open-drain FET solid state output, with source connected to D.C. common, provides an output for each channel. A 478 volt zener diode is connected across the source and drain for transient protection.

Status Output Format: Status output format conforms to NEMA TS-2. Refer to operator's manual. Operating Power: 10.8 VDC to 26.5 VDC, 80 milliamps maximum.

Operating Temperature: -40° F to +180° F (-40° C to +82° C)

Size: 4.5" H x 6.875" L x 1.12" W (11.4 x 17.5 x 2.8 cm). Edge card connector is centered on the 4.5" (11.4 cm) edge.

Weight: 7 oz. (198.4 g)

Connector: 2 x 22-pin edge card connector with 0.156" (4 mm) contact centers. Key slots are located between B and C, E and F, M and N.

Pin Assignments: (P1) (Under Construction)