When drivers pull on to a truck scale, there
often needs to be some
form of communication so they know what's expected of them. There
are a variety of solutions for truck scale
intercoms that can be tailored to the unique
installations of each of these scales. These
solutions will be discussed here.
First let's cover the problems encountered
that are common among many truck scales:
-
Trucker's arms aren't long enough,
unless the truck is driven by a gorilla.
The mirrors on
most trucks stick out quite far, and
since truckers don't want to hit
the intercom when they are driving up,
their arms aren't long enough to push a button without
getting out of the cab. In some cases
that's not a problem, but we will cover
solutions for both instances.
-
Engines of the trucks are quite loud. If
the driver stays in the truck then
whatever intercom solution is chosen
needs to have ample volume to overcome
the engine noise.
-
Some truck scales accommodate trucks of
all sizes so at what height do you put
the intercom? A pickup truck
driver would need the neck of a giraffe
to talk into an intercom on a pole for
an 18 wheeler, or vice versa.
-
There may be obstructions such as
concrete, railroad tracks, or other
obstacles that make running wire next to
impossible. In this case, you'll have to
rule out wired systems and go with a
wireless truck scale intercom system. If
you go with a wireless system, the truck
itself may be an obstruction to the
signal. There are ways and systems to
overcome this.
-
If you can only install a wireless
system and there's no AC power near
where the intercom will be installed,
then you'll need a solar power system to
go with the intercom.
-
You may not always have staff watching
for trucks arriving so how do you know when
one pulls up? That's where some sort
of notification system is needed.
-
If you have trucks of varying lengths,
and they stop in different places, where
do you put the intercom? This is
something you may need to address with
signs.
-
Of course money may be an issue too so
that could limit what type of system you
can choose.
There are the
solutions to each of the problems above that
will be discussed below.

1.
Driver Arm Length
If you can
install a wired system, there are intercoms
that use loud horn-type speakers that also
act as the microphone as well. You can
install a button so the driver can call the
scale house, but this isn't necessary as
long as someone knows the truck is there and
can call out to it. If the operator
needs to be alerted of an approaching truck,
then a photo eye that rings a bell could be
installed. To talk to the driver, the scale
house operator just presses a Push-to-Talk
button on the inside intercom, and the truck
driver can then talk hands-free.
If you need a wireless system and the driver
can't get out of the truck, then we
recommend a full-duplex wireless system that
has the ability to automatically activate
its transmit capability when a photo beam is
broken. So when the driver pulls up, the
system goes into transmit and receive mode
on both sides and both parties can carry on
a conversation. After the call, the system
times out and waits for the next truck.
If the driver can get out of the truck and
push a button to talk, then a wireless
callbox can be used to communicate with the
scale operator. What's beneficial about this
application is that the scale operator can
use a handheld two-way radio to talk to the
drivers so he or she doesn't have to be confined to
one location. You could also use a
basic wired intercom system as well since
the driver is likely away from the noise of
the truck.
If you don't need the driver to talk at all,
a public address system could be used to
broadcast messages. There is even a wireless
PA system that would enable your scale
operators to use handheld two-way radios to
broadcast messages to the truckers. These
systems have a range of a mile or more so
the operator wouldn't need to even be
anywhere near the scale. There is a wireless
alert device available that could alert the
operator that a truck is on the scale.
2.
Noisy Engines
For a wired system this is where a loud horn
speaker helps overcome the noise of the
truck. For the wireless system the
full-duplex intercom has noise cancellation
built in, plus a speaker that gets loud
enough to communicate over most engines.
3. Truck
Height
If the driver
doesn't have to push a button, you can mount
the intercom or horn speaker somewhere in
between the differing heights and you should
be OK. If you use a system that does require
button pushes, then there is a 72" & 42"
Dual-Height, Pad-Mount Pedestal Pole where
you could mount two intercoms.
4.
Obstructions
Depending on the scale installation, it may
be virtually impossible, or at least far too
expensive, to install cable for a wired
system. Trying to bore or cut through metal,
asphalt, or concrete can add thousands to
the installation cost.
However, there can be obstructions for a
wireless system as well. Buildings, hills,
or even the truck itself are obstructions.
The best signal will be obtained with clear
line of sight between the inside and outside
units. It's not absolutely necessary to be
able to see between points since radio
signals do bounce around. But, your chances
of success will be reduced, especially if
you go with a full-duplex intercom that uses
900mHz as its frequency. 900MHz systems have
lower power than a system that uses VHF or
UHF, but the feature set is greater and may
be needed. There are ways to overcome the
obstructions by raising the antenna height
over the truck, or by installing high gain
antennas mounted as high as possible. If you
want to learn more about how far wireless
communications can reach, the article and
video at this web address will help:
www.intercomsonline.com/range
5.
Solar Power
If you can't run wires, you also may not be
able to get power to the location where you need
the intercom. A self-contained solar power
system may be your only option. What wattage
solar panel you choose depends on several
factors, but the greatest will be determined
by the number of trucks that run through the
scale daily. If you have 200-300 trucks a
day, a 50-watt system will likely do it for
you, while fewer trucks than that you can probably
get by with a lower wattage system as long
as you don't have cloudy days for days on
end.
6. Roaming
Staff
If your scale
operators are roaming around, you'll need
some way of notifying them that a truck as
arrived. If they are far away from where
they need to be, then you may want that
notification to occur even before the truck
has arrived so the operator can get back to
the scale house. You could install a motion or photo beam sensor earlier in the
path of the truck. But if you are using a
full-duplex intercom that automatically
turns on then you'll still need detection at
the intercom system as well.
7. Truck
Length
If the trucks coming on to your scale are
pretty much all the same length, then where
you put the intercom depends on where you
want the trucks to stop. If they are varying
lengths then you may need to put the
intercom towards the front of the scale as
long your scale measures accurately with
small trucks this way. Regardless, you may
need signs to tell truckers where to stop.
8.
Budget
Wired systems are the lowest cost but you
have to factor in the labor cost to run
wire, which can be astronomical. A full
duplex wireless system is very expensive,
but depending on the features you need, it
may be your only choice, and it still may be
less than the labor cost of installing a
wired system. If you have to go with solar
power that's going to add quite a bit to the
cost as well. Either way, wired or wireless,
installing a system may save you money in
the long run through increases in
productivity and efficiency.
Contact the
intercom experts at
www.IntercomsOnline.com and we can help
you choose the right truck scale intercom
system for your unique application.
To download this whitepaper, click on the
cover graphic to the right.