When I bought my first car, I didn't care about maintenance at all. Instead of carefully checking the oil and watching the wear on my tires, I drove it mindlessly into the ground. However, after junking my first car after only five years, I learned how painful it was to start the entire process from square one. The fact of the matter is that car repair is important. In addition to keeping you safe, car repair can also save you money. As you look through the articles on my website, I hope that you can find tips to help you along the way, so that you can hang onto your investment.
If you are new to purchasing commercial trucks for sale, then you probably know there is a lot to learn about the entire process. Buying a car may be similar in some ways, but there are certain aspects you will want to pay closer attention to when looking for a used semi truck. One of the things you may not have thought about much is the truck's electrical system, particularly the batteries. Below is more information about semi truck's batteries that helps you understand their unique operation within a tractor as well as a couple of key battery variables that will help you identify the best options:
Semi truck batteries and electrical system
Semi trucks utilize batteries that look familiar to the average car owner in terms of appearance, but there is more than meets the eye when it comes to them. To begin with, most semi trucks have at least three, often four, batteries wired together in a hybrid series/parallel circuit. A series circuit is one in which the compiled voltage of the batteries is added together; in parallel circuits, the batteries are wired in such a way that the voltage remains the same as it would in one battery. The hybrid nature of a semi truck's electrical system permits both high voltages and a deep reservoir of power when needed.
Most semi trucks combine voltages in a series circuit to produce 24 volts for turning over the truck's starter motor; this is necessary due to the heavy weight of the engine's crankshaft and the high compression generated by diesel engines. However, 12 volts of output is sufficient for powering accessories that are operated by the battery. When you are looking a particular truck, you should make a note about how many batteries are used; the more batteries, the more power reserves you will have available. Of course, this will also increase your expense if you need to replace all the batteries, so weigh that against the benefits gained by having an extra battery or two.
Battery types
The traditional battery type available in semi trucks, as well as most passenger vehicles in the United States, is the lead-acid type. Lead-acid batteries are powered by a chemical reaction between lead sulfide plates and fluid electrolytes; this reaction results in a transfer of electrons which, in turn, generates current. Older types of lead-acid batteries require periodic refilling with water to keep the electrolyte at its optimal level.
Newer batteries are moving away from the traditional lead-acid paradigm that requires the addition of water. Instead, sealed batteries are now commonly used. One of the latest technologies that is proving to be a boon for truck drivers is the development of absorbed glass mat (AGM) batteries. Instead of using a free-flowing liquid electrolyte, a mat made from glass fibers absorbs the electrolyte and holds it in place, ready for use. The entire unit is sealed, and there is never a need for a driver to open it. This greatly reduces the need for periodic water refills, and the sealed nature of these batteries protects the driver from hazardous discharges and fumes. The drawback to AGM batteries is expense; they cost approximately double the price of non-sealed units.
Another note to make while looking at a truck is to see what kind of battery is in-place. If you don't see any way to access the interior of the battery through snap-on and off lids, then it is probably sealed and will not require maintenance; in addition, look for the words that indicate it is an absorbed glass mat battery. Chances are good this battery will have a lot of useful life remaining, if it is an AGM type.
Cold cranking amps
If you have ever browsed an automotive parts store, you likely have seen the various car batteries on display. You may have noticed a rating known as cold cranking amps (CCA) as well as its companion measure, cranking amps (CA). Cold cranking amps informs you how much power is available to power a starter at zero degrees Fahrenheit, while cranking amps measures the same except at 32 degrees Fahrenheit.
These measures are important to truck drivers because they indicate the sufficiency of a battery to provide current for a starter motor for a given length of time. A new battery with higher CCA and CA ratings will hold-out longer than other new batteries with lower ratings. With strict regulation of idling times becoming widespread, that means your semi truck is going to need to be started more often than trucks just a decade or two ago. If you purchase a semi truck that contains batteries with fewer than 1,000 CCA, you should carefully consider if they will be sufficient to meet your needs. Be sure to factor in the cost of replacement batteries when negotiating the purchase.
Share9 March 2015
