45
MARCH 2014
ACCESS, LIFT & HANDLERS
Manual vs. automated
Fred Wehmeyer
, senior vice
president of engineering
at U.S. Battery
Manufacturing, discusses
the facts on which
battery maintenance
technique can actually
lower your fleet’s annual
operating costs
W
ith increased competition, along with
a demand for “greener” alternatives
and lower prices, more rental fleets
are using battery powered equipment than ever
before. Booms and scissors powered by flooded
lead-acid batteries provide many rental fleets
with the capability of offering lighter and more
compact equipment, along with the benefits of
reduced annual fuel costs. So it’s important for
rental fleets to realize that extending battery
life with proper maintenance can improve their
bottom line.
Most fleets with battery-powered equipment
already know that it’s necessary to charge and
add water to flooded lead-acid batteries. Cutting
costs by deciding to add water manually, versus
using a more expensive automated watering
system, doesn’t necessarily mean it’s saving
you any money in the long run. Some fleets use
a garden hose for watering which could actually
be damaging the batteries and reducing their
life expectancy. Yet many fleets think they’ll
save additional costs on maintenance time and
equipment doing it this way.
It’s important to know that no battery
manufacturer recommends using a garden hose
to refill the water in any deep-cycle battery and
this practice can affect warranty coverage. If
you must water manually, make sure to use
only distilled water and take careful electrolyte
level measurements. Use a water delivery gun,
watering pitcher or at the very least, some type
of measuring cup to ensure you’re delivering
the right amount for each cell. The electrolyte
should be kept about 1/4-inch below the bottom
of equipment with an automated watering
system, mostly because no vent cap removal
and replacement is required on the battery pack
for each unit. For the same size fleet, watered
once per month, the maintenance time per year
is reduced to 20 to 40 hours at a cost of $300
to $600 per year. That’s a reduction in cost of
$1,500 to $3,000 annually or $7,500 to $15,000
over a five year life expectancy of the batteries.
With the price of a watering system averaging
about $100 per piece of equipment, the upfront
cost can be a big investment. But when you
consider that the expected life of a watering
system is somewhat longer than five years,
the numbers shift in your favor. Many fleet
managers utilizing a watering system claim they
can get 10 years out of them with a moderate
level of maintenance and replacement parts.
With this type of investment, a rental fleet could
expect the payback period to be three to seven
years with extended battery life as a bonus.
So, for larger fleets, the upfront cost of
a watering system can make a significant
difference in the long run. However, since not
every fleet is the same, you’ll have to figure-in
your numbers for yourself to see what’s best
for your particular fleet. Check the websites
on various watering system manufacturers.
They often have an online calculator that can
help measure your return on investment. The
overall goal is to increase the life of your fleet’s
batteries. When you do, you’ll see some real
savings that might change the way you think
about battery maintenance and the importance
of carefully watering them.
■
of the fill-well in the battery’s cell cover.
Watering systems, on the other hand,
automatically and precisely fill multiple batteries
at once, providing each battery cell with the
correct amount of water.
Automatic H
2
0
Initially, they are more expensive, but for a
fleet with many batteries to maintain, watering
systems are easier to use and can reduce
the down-time for your fleet. Even though
automated watering systems are not used for
every fleet, operators should determine which
method is more cost effective by determining
how often the batteries must be watered and
the amount of time and cost it takes to water
the entire fleet. On average, medium to heavy-
duty scissor lifts and aerial work platforms
should have their batteries watered at least
once per month.
Watering batteries manually usually takes
about 15-30 seconds per cell and typically
involves removing the vent caps, watering
using a watering pitcher or water caddy, and
replacing the vent caps. For example, for a
single 48-volt scissor lift, this would translate to
approximately 6 to 12 minutes per lift. Multiply
that times an average fleet with approximately
100 battery powered pieces of equipment, and
watering once per month translates to 120 to
240 hours per year. Not bad, but also add in
$15 per hour for an average technician, and
your maintenance costs can average $1,800 to
$3,600 per year.
The time is reduced to 1-2 minutes per piece
Watering systems, like this
one pictured, automatically
and precisely fill multiple
batteries at once, providing
each battery cell with the
correct amount of water.
BATTERIES
