EMX Industries VMD202 User manual

VMD202
V E H I C L E M O T I O N D E T E C T O R
The VMD202 vehicle motion detector senses moving
ferrous metal within its magnetic field. It has a
detection range up to 3.5 m at a minimum speed of
8 km/hr. An optional sensitivity remote finely tunes
the VMD202 to fit any installation requirement and
then easily detaches to prevent unwanted changes
or tampering. The settings are stored in a non-
volatile memory, saving them in case of power
failure. The VMD202 accepts a wide range of power
inputs from 12-39 VDC or 12-27 VAC and features a
low current consumption (70 uA standby / 25 mA
activated) making it ideal for solar applications.
VMD202

Vehicle Motion Detector
• The probe assembly and cable are water tight and direct burial compatible.
• An optional remote can be connected via screw terminals to select 10 sensitivity settings.
• The detection range is up to 3.5 m at a minimum speed of 8 km/hr.
12-39 VDC or 12-27 VAC
70 uA standby / 25 mA activated
Form C (SPDT) 1A@24 VDC; 1A@120 VAC
o o o o
-30 C to 70 C (-22 to 158 F) 0 to 95% relative humidity
ABS plastic for VMD202-R, PVC for probe
VMD202-R 2.9" (74 mm) x 1.7" (35 mm) x 0.6" (15 mm)
5 wire direct burial PVC
Power
Current
Relay
Operating Temperature
Material
Remote Dimensions
Probe Cable
Technical Data
Ordering Information
VMD202
VMD202-R
VDM202 24" (610 mm) x 1" (25 mm)
Probe Dimensions (L x Dia.)
WARRANTY EMX INC. the product described herein for a period of 2 years under normal use and service from the date of sale to our
customer. The product will be free from defects in material and workmanship. This warranty does not cover ordinary wear and tear,
abuse, misuse, overloading, altered products, or damage caused by the purchaser from incorrect connections, or lightning damage.
There is no warranty of merchantability. There are no warranties expressed, implied, or any affirmation of fact or representation which
extend beyond the description set forth herein. EMX Inc. sole responsibility and liability, and the purchaser’s exclusive remedy shall be
limited to the repair or replacement at EMX’s option of a part or parts not so conforming to the warranty. In no event shall EMX Inc. be
liable for damages of any nature, including incidental or consequential damages, including but, not limited to any damages resulting
from non-conformity defects in material or workmanship. Rev 1.3 01/04/2021
• VMD202-15 Prop with 15m of cable
• VMD202-R Remote for tuning and adjustment control

VMD202™
Single Piece Vehicle Motion Detector
And Sensitivity Remote
Instruction Manual
Cautions and Warnings
Specifications
Power 12-39 VDC or 12-27 VAC
Power Indicator Green LED (Sensitivity Remote Only)
Standby Current 70 uA
Detection Current 25 mA
Range Sensitivity 12 ft @ 5 mph min. speed
Sensitivity Adjustment 10 settings
Output Time 5 seconds
Surge Protection Probe input circuitry protected by surge suppressors
Relay Output Configuration Form C (SPDT)
Relay Contact Rating 1 A @ 24 VDC / 1 A @ 120 VAC
Operating Temperature -30˚C to 70˚C (-22˚to 158˚F) 0 to 95% relative humidity
Remote Housing Material ABS plastic
Remote Dimensions (L x W x H) 2.9” (74 mm) x 1.7” (35 mm) x 0.6” (15 mm)
Remote Weight 0.05 lbs (23 g)
Probe Housing Material PVC watertight
Probe Dimensions (L x Dia.) 24” (610 mm) x 1” (25 mm)
Probe Cable 5-wire, direct burial
The VMD202 is a compact, single-piece vehicle motion detector that operates by detecting changes in the
earth’s magnetic field that occur near the probe. It has a detection range of up to 3.5m at a Minimum
Speed of 8 km/h. The VMD202 will only detect a moving vehicle and will not detect a stationary vehicle. It
may be used as a free exit sensor to allow gates to open and guests to exit without the use of a key fob
or passcode. The VMD202 may also be wired to notify a home automation system or security system that
a vehicle is moving down a driveway.
The VMD202 is designed to detect moving vehicles. It is not suitable for use as a vehicle
presence detector such as a reversing loop for a gate or door.
The VMD202 detects ferrous metals. It will not detect aluminum but will detect any
moving ferrous metallic object.
The probe must be stationary to function properly.

Ordering Information
Controls and Indicators
Sensitivity is a function of speed and mass. The smaller a vehicle is and the slower it is
moving, the closer it must pass the probe to trigger the detector.
Wiring Connections
Probe Connections
Wire Color Description
Red Power + (12-39 VDC or 12-27 VAC)
Black Power – (12-39 VDC or 12-27 VAC)
Green Relay – COM (common contact)
White Relay – NC (normally closed contact)
Brown Relay – NO (normally open contact)
Remote Connections
Terminal Description
Probe PWR + Power out to probe (Probe Red Wire)
Probe PWR – Power out to probe (Probe Black Wire)
Earth GND Earth ground connection
Operator PWR + Power in from operator (12-39 VDC or 12-27 VAC)
Operator PWR – Power in from operator (12-39 VDC or 12-27 VAC)
TIP:
VMD202-15 - Advanced Gate Automation Vehicle Motion Detector with 15m Cable
Vehicle Motion Detector VMD202 with 15m Cable and VMD202-R Sensitivity Remote
Suitable for 12-39 VDC / 12-27 VAC and Solar Power Applications

5
Applications
Standard Applications:
Solar Applications:
The remote control is removed to minimize power consumption.
*Values are without remote connected
Number of Vehicle
Activations Per Day
Average Current
(Amps)
720 0.001442
288 0.000619
144 0.000344
72 0.000207
48 0.000161
IMPORTANT: EARTH GROUND CONNECTION
The VMD202 contains protection devices to guard against damage and false triggering due to electrical
transients caused by lightning or other sources. Always provide a good earth-ground connection to the green
wire of the VMD202 remote control in standard applications or the black wire of the VMD202 probe in solar
applications. A 20cm copper rod or metal cold-water pipe provides a sufficient earth-ground connection.
SOLAR NOTE: The probe consumes only 70 uA when no vehicle
motion is detected and draws a higher current for 5 seconds
when detecting vehicle motion. This table provides an average
current draw based on an estimate of how many cars per day
may activate the VMD202. Connect the remote to the probe to
adjust the sensitivity, then remove the remote and power the
probe directly from the operator (the remote draws extra
current). A 12 VDC battery is recommended for solar applications
(a 24 VDC battery can be used as well).

Read the following list of tips prior to beginning the installation process.
This will save significant time in the long run.
•
Size of Moving Vehicle Speed Detection Distance
Average size car or truck 8 km/hr min. Up to 30 cm
Average size car or truck 16-80 km/hr Greater than 30 cm
Large truck or semi-truck Over 80 km/hr Greater than 1 m
Train Any 2.5 m
• The detector is sensitive to minute changes in the magnetic field around the probe.
Power lines, transformers, and other electrical devices located in the vicinity of the probe
that produce transients could cause disturbances in the magnetic field that may result in
triggering the detector. Avoid installation of the probe near these devices.
• Do not install the probe or lead wire near or parallel to:
• Low voltage lighting wires or in-ground power lines
• Telephone lines or intercom systems
• Electric motors or control relays
• Overhead power lines, transformers, or underground power lines
• Cell phone towers, TV towers or communications links
• Moving metal flagpoles, fences, gates, or horses with metal shoes
• Do not mount on any moving surface, such as bridges or walkways that may vibrate under traffic.
The probe must always be installed in such a way that it remains completely motionless.
Any movement will cause the probe to trigger.
• Probes are available in various cable lengths, when possible select the appropriate cable length
for the installation. If it is necessary to extend the cable length (maximum 15 m) use a
high-quality lead-in cable suitable for direct burial and a high quality, watertight cable splice
to prevent moisture from entering the cable causing false triggering. Lead-in wire is available from
EMX.
• When there is a high incidence of damage from burrowing animals or other potential damaging
activities, it is recommended that the cable be placed in plastic conduit (3.8 cm internal diameter).
Damage to the cable jacket may allow moisture to enter the cable causing false triggering. When
placing the probe in plastic conduit, use foam or tape to assure that the probe
does not move or vibrate. It is recommended that the conduit be sealed to prevent water from
collecting in it.
Installation
The detector’s sensitivity is a function of speed and mass. The detection distance for a moving,
average size car or truck is approximately 3.5 m at a speed of 8 km/hr. At higher speeds, the
detection distance can exceed 3.5 m as noted below.

Installation Methods
Adjacent to Roadway (Recommended Method) In a Roadway
1. Temporarily place the probe parallel to the
roadway (driveway) in the desired location.
1. Position the probe in the center of the
roadway, perpendicular to the direction of
traffic. The probe should be located at a
minimum of 5cm deep in concrete or asphalt.
• If installing the probe prior to paving a hot
asphalt roadway, the VMD202 and its lead
cable need to be insulated. A common
method to do this would be to dig a small
trench and bury the probe and lead cable in
10cm of sand prior to paving.
(DO NOT APPLY
HOT ASPHAULT DIRECTLY AGAINST
PROBE AND LEAD CABLE!)
• If installing the probe in concrete, make sure
it is installed above the rebar.
• The probe may be positioned prior to paving
or a cut may be made in the finished
pavement for installation.
2. Connect the power, VMD202 remote control, output relay contact and earth ground to the
intended equipment. (Reference EARTH GROUND CONNECTION in Wiring Connections.)
DO NOT EXCEED 39 VDC or 27 VAC.
3. Apply power and allow 5 minutes of warm-up for system stabilization.
4. Set sensitivity to 0.
5.
Drive a vehicle at a minimum speed of 8 km/hr passed the probe and to the far side of the roadway.
6. Repeat step 5 while gradually increasing the sensitivity until the system detects the vehicle.
•
•
7. 7. Installation in roadway complete.
For instances of high pedestrian traffic, heavy animals or heavy vehicles, bury the probe
60 cm deep to prevent false triggering in either installation method.
TIP:
TIP:
TIP:
15m CABLE
GATE OPENER
JUNCTION BOX “BY OTHERS”
VMD202 PROBE
BURIED 20-30 CM DEEP
SENSING AREA - APPROX. 3.5M
DIAMETER CIRCLE AROUND PROBE
A higher sensitivity setting than required to detect the vehicle makes the system more
vulnerable to triggering from unintended sources such as movement of other objects,
including bicycles, horses, small vehicles, metal in shoes or other electrical disturbances.
When the detector is set to maximum sensitivity (full counterclockwise on the sensitivity
adjustment) detection distance is approximately 3.5m at a speed of 8 km/hr. At higher
speeds, 15-20 km/hr, detection distance can exceed 3.5m.
Bury the probe at this location approximately
20-25 cm deep for typical applications. Repeat
the previous sensitivity check (steps 4-5) to
verify proper operation. Installation is adjacent
to roadway complete.

Symptom Possible Cause Solution
False triggering Electrical disturbances
Damaged probe cable
Moisture in probe cable
Movement in the probe’s
environment
Dirty or noisy power supply
Lightning
Low Input Voltage
1. Verify that the earth ground connection to the
VMD202 is secure. If the connection is not secure,
reconnect both the VMD202 and the
earth ground and retest the system.
2. Disconnect the relay wires (green, white, brown)
and see if the false triggering continues. If the false
triggering stops, check the probe as outlined below
in step 3. If the false triggering continues,
disconnect the power and temporarily connect a
12V battery to the VMD202 and reconnect the
probe. Wait 5 minutes for the system to stabilize. If
the false triggering stops, consider using a separate
power supply for the VMD202 such as a 120 VAC to
12 VDC power converter (min. 100 ma). Reconnect
the probe and retest the system.
3. Inspect the area around the probe to see if any
ferrous metal objects may be subject to any
movement. These may include fences, flagpoles,
signs, etc. Other possible causes are electrical
power lines, electric motors, invisible dog fences,
low voltage lighting and high-power lighting.
No output Bad wire connection
Failed relay
1. Disconnect the output contacts from the operator.
2. Connect a digital multimeter, set to read ohms, to
the COM and NO contacts. The meter should read
open (infinity, or “OL”).
3. Move a metal tool over the length of the probe.
Verify that the meter reads less than 10 ohms. If the
meter reads more than 10 ohms, the VMD202 is
defective.
No detection Minimum 8 km/hr
Bad wire connection
Faulty power connection
Failed relay
1. Verify that the VMD202 remote control’s
green LED is on. If not, check the supply voltage
using a digital multimeter. Verify the voltage is
12-39 VDC or 12-27 VAC.
2. If voltage is present and there is still no detection,
the VMD202 is defective.
EMX Industries, Inc. products have a warranty against defects in materials and workmanship for a period
of two years from date of sale to our customer.
Troubleshooting
Warranty

VMD202™
Single Piece Vehicle Motion Detector
Sensitivity Remote
Guide: Removing VMD202 Probe Harness for Remote w/ Terminals
Required Tools: Wire strippers, small flat-head screwdriver
Wiring to Remote and Operator
• Wire the Red (Probe PWR +) and Black (Probe PWR -) wires from the probe cable into the
two remote screw terminals labeled “Probe PWR”.
• Wire the probe relay wires (Green=COM, White=NC, Brown=NO) to the operator input terminals.
See the operator’s manual for wiring instructions.
• Wire power (12-39 VDC / 12-27 VAC) from the operator into the remote terminals
labeled “Operator PWR”. Ensure power is wired in with the correct polarity. Incorrect wiring
can cause permanent damage to the remote. The operator power cable is not provided with the
VMD202 system.
• If the remote is going to permanently be part of
the installation, connect an earth ground to the
remote terminal labeled “Earth GND”.
Probe Connections
Wire Color Description
Red Power + (12-39 VDC or 12-27 VAC)
Black Power – (12-39 VDC or 12-27 VAC)
Green Relay – COM (common contact)
White Relay – NC (normally closed contact)
Brown Relay – NO (normally open contact)
• The image to the right shows how the final wiring
should look. If you intend to use the VMD202 without
the remote, use the table below for connections to the
probe cable.
Final Wiring to the VMD202 Remote