Snapshot of a Pulsor Installation
For more details, here is the
How Pulsors Work
- Each Pulsor is a solid state piezo-resistive semi-conductor with a
stable resistance value. When strain is applied, its resistance
changes dramatically, much like a step change, returning quickly to its
- By expoxying a Pulsor to the bottom of a floor beam (joist),
the strain needed to produce this step-change is limited to a
compressive load applied to the area of the floor above the Pulsor.
- The Pulsor's structural compression sensor is epoxied to the bottom of
a support beam or floor joist. Each Pulsor is wired back to a
master processor located at the control panel.
- As an intruder enters the protected area, his weight casuses
compression and flexing along this beam. The sensing
semi-conductor momentarily changes resistance causing a voltage signal
to be sent to the processor. This signal is altered, amplified,
and analyzed. It is then converted into an alarm out signal (dry
contacts) to the control panel.
Placement of Pulsors for Maximum Efficiency
- Consider Pulsors as miniature motion detectors protecting an area of
the floor. Try not to use them as perimeter devices covering only
- Place Pulsors in traffic areas through which an intruder would pass
(front hallway for example).
- Distribute Pulsors throughout the house providing protection even
for non-target areas such as guest bedrooms and kitchens.
- Protect the 2nd floor by concealing a Pulsor above a 1st floor smoke
or heat detector.
- Protect the 2nd floor stairs by placing a Pulsor at the bottom edge
of a riser near center of staircase.
- Pulsors may be placed in front of entertainment centers, cabinets,
etc., to provide specfic protection.
- Contacting a few selected perimeter doors may allow the Pulsors to
be placed further into the interior of the house for more effective
- When determining Pulsor locations in a new house, the furniture
location must be considered. Locations under furniture are not
Pets and Pulsors
Pulsor systems can be used in houses allowing small dogs and cats to roam
freely with the following considerations:
- Avoid Pulsor locations that are near tables or furniture from which
the pet may jump.
- Avoid areas where the pet may become excited, such as the front door
area, near glass doors, etc.
- To prevent the animal's weight from tripping the Pulsor, perform a
careful walk test.
What to Avoid
- Placing long runs of wire parallel to AC electrical cables.
- Installing on beams (joists) that are flexed by walking outside the
- Installing on beams that are not secured at each end.
Hints on Pulsors Installation
There are moments when the ENHP+ Pulsor is not sensitive enough for all
or parts of an application. Switch to the HPP+ Pulsor when The
following conditions exist:
- Double beams or sister beams
- 12" joists
- Manufactured laminate beams
- Pulsor placement is less than 3' from edge of joist
- Floors are pre-stressed by heavy appliances
How to Install a Pulsor
Clean bottom of joist with a scraper or sandpaper.
- Mix epoxy on non-porous surface and immediately apply generously to
bottom of Pulsor.
- Use tape, without pressure, to hold Pulsor in place while epoxy sets.
Place tape at the edges of the Pulsor; avoid stressing the center of the
- Strip and crimp to the circuit cable using the epoxy-filled crimps
provided. Note that bare wire left exposed is not acceptable.
- Allow epoxy 4-hours to harden before walk-testing. The area
can be walked on immediately, but it is important to give the epoxy time
to set before testing the sensor.
- It is recommended to measure each Pulsor's resistance after it is
attached to the beam and crimped to the cable. Use a quality
digital multimeter and keep a record in the control box for future use.
- Each attached Pulsor will read approximately 1000-OHMS +/- 30%.
This value will not change appreciably over time.
- Pulsors are not delicate. However, they can be damaged by
rough handling. Avoid bending any unit and do not press hard on
the center when installing a unit on a beam.
- Epoxy has good gap-filling properties and does not require heavy
clamping to form a good bond.
- Always maintain the lowest senstivity adjustment.
- Set Adjustment for a 7-foot capture along the joist and 4 feet
across the joist. However, if floors are stiff, range can be
increased. A 14' x'14' room uses one Pulsor and a 14' x 22' room
uses two Pulsors.
- For normal operation sensitivy jumpers are to be removed.
Install only when absolutely necessary.
- After the epoxy has set for 4 hours, it is important to test the
system to ensure you have the desired oval of detection and sensitivity.
- Full sensitivity is reached after 24-hours. Doing the walk
test at 4 hours, gives a good indication of what the sensitivity will
If proper installation techniques are used, false alarms will be
virtually eliminated. If problems do occur after the installation, the
following troubleshooting methods should be followed.
- First step is to remove the Pulsors from the processor. Take
the resistance reading of the Pulsors and reinstall them having the
highest and lowest reading sensors between A and C, and the other
sensors in series between c and B. Then, take the voltage reading
between C and minus of power. The perfect reading would be 2.48.
The acceptable range is between 2.4 and 2.6 VDC.
- Measure the resistance of each Pulsor (disconnect at control) and
compare to original record. Note, any large changes in resistance
reading of the individual Pulsor (1000-OHM +/- 30%). Any Pulsor
that differs by 400-OHMs to 500-OHMs from its original reading from the
other units in this system may need replacement.
- Walk-test each Pulsor, observing the resistance with a digital OHM
meter. Note the resistance change. A change of as little as 5-OHMs
will trip the processor. Therefore, a Pulsor that shows an excessive
resistance change when walked over (greater than 100-OHMs) may be too
sensitive. Reduce sensitivity at the processor.
- With the above test the Pulsor's resistance should return to within
a few OHMs of its original value. If not, replace the Pulsor and
use only a good 5-minute epoxy for bonding.
- Any Pulsor that is suspect may be temporarily replace by a 1000-OHM
resistor. If the system stabilizes (no false alarms) carefully
examine location for excessive sensitivity or outside interference
and/or replace the Pulsor.