US Automatic 070305 CP4 Free Exit Vehicle Sensor Kit
The US Automatic 070305 CP4 is a self-contained free-exit vehicle sensor designed to trigger a gate opener when a moving vehicle passes near the buried sensor. Instead of cutting a saw-cut loop into the driveway, the probe is normally installed beside the drive lane and wired back to the gate operator. The CP4 detects changes in the magnetic field created by moving vehicles, then sends a relay contact to the operator control board. It is commonly used on residential driveway gates, farm and ranch gates, small commercial gates, and solar-powered gate systems where low standby draw is important. Because it is a vehicle exit device, it should be wired to the correct open, exit, or free-exit input and should not be used as a pedestrian safety device or as a replacement for monitored entrapment protection.
Compatible With
- US Automatic Patriot swing gate operators with a compatible exit/open input
- US Automatic Ranger HD swing gate operators with a compatible exit/open input
- US Automatic Ranger 500 swing gate operators with a compatible exit/open input
- US Automatic Patriot RSL slide gate operators with a compatible exit/open input
- Select Sentry 300 series and older US Automatic/Sentry systems when the control board accepts the required relay input and power range
- Most residential and light commercial gate operators that accept a dry-contact SPDT exit relay signal
- Solar or AC charged gate systems when power is within the sensor range and wiring is installed correctly
- Can be adapted to many brands such as Linear, Mighty Mule, LiftMaster, Viking, DoorKing, Apollo/Nice, and others when the operator input, voltage, and relay wiring are confirmed
Features & Specifications
| Manufacturer | US Automatic |
| Product Type | Free exit vehicle sensor kit |
| Part Number | 070305 |
| Common Model Reference | CP4 |
| Application | Vehicle free-exit detection for automatic gates |
| Compatible Operator Type | Swing and slide gate operators with compatible exit/open inputs |
| Power | 8-24 VAC or 8-30 VDC commonly listed for CP4 style sensors |
| Relay Output | SPDT dry contact with normally open and normally closed wiring options |
| Cable Length | 100 ft cable commonly associated with the kit |
| Detection Type | Magnetic moving-vehicle detection |
| Notes | Exit sensor only; not a monitored gate safety device |
Also Known As / Related Part Numbers
- 070305
- CP4
- US Automatic CP4
- USAutomatic CP4
- Cartell CP-4
- Cartell GateMate free exit sensor
- 5-wire exit wand
- 5 wire exit wand
- free exit device
- vehicle sensor kit
- exit vehicle detector
- magnetic free exit probe
- driveway exit sensor
Technician Note
Install location is critical. The probe should be placed where vehicles pass within the detection range but where gate movement, large stationary metal objects, buried utilities, or nearby traffic will not cause nuisance openings.
Before Ordering Checklist
- Confirm the gate operator has an available exit, open, or free-exit input
- Confirm the operator can supply 8-24 VAC or 8-30 VDC, or provide a proper power source
- Decide whether normally open or normally closed relay wiring is required
- Verify the driveway layout allows the probe to be installed next to the drive lane
- Do not use the CP4 as a monitored safety photo eye or reversing edge
- Plan conduit, splice protection, and surge protection before trenching
Professional Advisory
A free-exit sensor should be installed and tested as part of a complete gate system. If the gate has missing photo eyes, missing monitored edges, unsafe closing movement, or high-voltage wiring issues, have the system inspected by a qualified gate technician.
Important Ordering Warnings
- Do not wire the CP4 to bypass a safety input
- Do not rely on the CP4 for pedestrian detection
- Improper placement can cause false openings or missed vehicle detection
Product Questions & Answers
What does the CP4 free exit sensor do?
It detects a moving vehicle leaving the property and sends a relay signal to open the gate automatically.
Is the CP4 only for US Automatic gate operators?
No. It is commonly used with US Automatic operators, but it may also be used with other gate operators that support the required power and dry-contact relay input.
Does the CP4 replace a driveway loop detector?
It can be used instead of a traditional saw-cut exit loop in many driveway layouts, but it is a different detection method and must be installed in the correct location.
Is this a gate safety device?
No. The CP4 is an exit activation device. It does not replace monitored photo eyes, monitored edges, or other required entrapment protection.
Why does the five-wire design matter?
The five-wire design gives access to power, ground, normally open, normally closed, and common relay wiring so the installer can match the operator input requirements.
