Floor scrubbers are a needed tool for keeping your floors clean. But as with any type of equipment they do require some maintenance to keep working properly. It can be frustrating when your scrubber is not working and a job needs to be done. Many problems can be avoided just by having the operator become somewhat familiar with the basic functions of the machine and the common issues that can come up. This and the previous blog puts a spotlight on some of the most common problems that can come up when using a scrubber. Most of these can be prevented by routine maintenance. In this installment we will look at two more issues that knowing about ahead of time can save time and money.
"My machine will only run for a few minutes and then the batteries are dead."
Over the years, our techinicians have heard this complaint countless times. Here's what to look for first. Sometimes it's not a battery problem; it's an operator problem. Make sure it is actually being plugged in to charge after it is used. After plugging the charger in, make sure it is actually powering up and charging. Can you see the amp reading display showing how many amps it is charging? Most newer machines come with onboard chargers. And amp reading should be seen if it is indeed charging. Notice the picture of this S.P.E. charger showing a reading of 7 amps.
On most machines, this amp reading should go up to 15 to 20 amps for several hours and slowly trickle down. When the machine has correctly charged a reading of 0.0A should be seen on this particular charger. Many floor scrubbers have external chargers. On these, observe that the ample gauge needle is showing charging amps such as this picture of a Lestronic charger.
Again, the needle on the charger will initially go up to about 20 amps and slowly work its way down as it charges. Other external chargers such as the Lester E series won't have a gauge, but instead will have 3 lights - green, yellow, and red. Make sure it is flashing yellow. This shows that it is charging. Red will indicate a fault and green will show when it has completed the charge.
On the onboard S.P.E. chargers, this is the display:
This is showing "bat" because the battery pack is not connected to the charger. Check to make sure the anderson connector connected to the charger is plugged into the battery pack. Also inspect the anderson connector to ensure that the contacts inside it are properly seated. Notice in this picture that the contacts are fully in place.
Check for one of these metal contacts to be pushed back, cracks in the red or grey plastic housing, and that the 2 anderson plugs are being fully connected together. This can be problem on the onboard or the external chargers.
If it is not charging, check the outlet it is plugged into for voltage. Is the circuit breaker tripped? Also check that the power cord for the charger is properly plugged in.
Now if the charger is charging properly and there is a run time issue, look at the batteries. First, check the battery cables. Is there corrosion on them? Take the cables off and clean the terminals to remove this. If they are overly corroded, it is time for new cables. With good cables now we can move on to check the batteries.
This is where it can get confusing for many. Lets try to make this as easy as possible.
Step 1. Make sure the batteries have been charged. Next, turn the vac motor on to create some load on the pack. This can do away with the "surface charger" that can be misleading. Putting a load on the batteries also helps to find the problem faster.
Step 2. Test the pack and each battery with a digital voltmeter. A voltmeter is needed to properly repair one's own equipment. Those reading this blog are probably trying to repair a floor scrubber and save a lot of money on costly repairs. The volt meter will come in handy for many other repairs that will be discussed in other blog posts.
With the vac motor running, place the lead of the volt meter on the entire pack. Find the pack by following the wires going from the scrubber to the battery pack. Black and read wires will be seen. Notice the black and red circles on this picture. Black is negative and red is positive.
In this example the machine is a 24v unit with two 12v batteries in series, so at least 24V DC should be seen even under a load.
If the pack voltage is falling under 24v (or 36v on a 36v machine) the batteries probably need to be replaced. Also check the batteries individually. Most larger scrubbers will use four or six 6v batteries. These should stay above 6v under load (6.1 or 6.2v under load). This is a very simple way to check out your batteries. There is more to testing out batteries that involves using a hydrometer, but that will be discussed in another blog. If the batteries are more than a couple of years old and they don't pass this simple meter test, new batteries are more than likely needed.
Deep cycle batteries only have a certain number of cycles in their lifetime. Our technicians have seen scrubber batteries last 4 or 5 years that were properly maintained and not heavily used. Most quality floor scrubber batteries, if used daily, will last 2 or 3 years. They will go longer than that but the run time quickly goes down. The key is proper maintenance. Never let the electrolyte level in lead acid batteries get low. Always make sure that it is over the top of the lead plates. Never leave the batteries discharged. This will ruin batteries very quickly.
Contact us for more information: 501-844-1811.