PRODUCT CATEGORIES


Measurements & Troubleshooting
1. 
How can I tell if a flooded battery is bad?
To determine if the battery in a system is experiencing a problem, disconnect all electrical loads, fully charge the batteries then disconnect all charging sources. Allow each battery in the system to stand on open-circuit for about one hour. Measure the voltage of each battery. If the battery voltage spread exceeds .15 volts for a 6-volt battery, or .30 volts for a 12-volt battery a problem is indicated. Battery voltage alone does not confirm a problem. When the voltage spread indicates a problem, confirmation is accomplished by taking electrolyte specific gravity readings using a hydrometer. If the specific gravity readings show a spread greater than .030 (30 points), give the batteries an equalization charge and re-test.

2. How can a flooded battery's state of charge be accurately measured?
The state of charge of a lead acid battery is most accurately determined by measuring the specific gravity of the electrolyte. This is done with a hydrometer. Battery voltage also indicates the level of charge when measured in an open circuit condition. This should be done with a voltmeter. For an accurate voltage reading, the battery should also be allowed to rest for a period of one hour minimum in order to let the voltage stabilize.

3. How far can I tilt my batteries?
For flooded batteries, 30 degrees from vertical is the maximum recommended tilt. AGM and Gel batteries can be operated vertically or horizontally.

4. Can I reduce my maintenance by not gassing my flooded batteries?
You will reduce the frequency of watering, but will cause a condition known as stratification where the specific gravity of the electrolyte is light at the top of the battery and heavy at the bottom. This condition results in poor performance and reduced battery life.

5. What is used to clean a battery and neutralize the electrolyte?
A solution of baking soda and water. Use 1 lb. of baking soda for every gallon of water.

6. What is the specific gravity of a fully charged flooded battery?
A hydrometer reading of 1.285 or greater indicates full charge for most Trojan batteries however for the Premium LIne 1.280 or greater indicates full charge. This value is based upon a specified temperature of 80°F (27°C). For temperature correction values, see the “Temperature” section of this FAQ.

7. What is the correct Specific Gravity of the Trojan Premium Line? I was told that Trojan changed the SG value for the Premium Line. Is this true? How do I determine the correct Specific Gravity of the Trojan Premium Line battery I already have purchased?
Yes, Trojan changed SG values of the Premium Line in March 2012 to avoid confusion over correct SG values for the Premium Line compared to the Signature Line however this change does not have any impact on life cycle performance. Trojan Premium Line batteries manufactured prior to March, 2012 have nominal S.G. of 1.260  while those produced after March 2012 have nominal S.G. of 1.280. To determine the date of manufacture, refer to the date code on the negative terminal which consists of a letter and a number. The letter refers to the month and the number refers to the year. A2 = January 2012, B2 = February 2012 and C2 = March 2012 etc.

Maintenance
1. What is the shelf life of my battery?
The limiting factor of battery’s shelf life is the rate of self-discharge which itself is temperature dependent. VRLA batteries will self-discharge less than 3% per month at 77º F (25º C). Flooded batteries will self-discharge up to 15% per month at 77º F (25º C). VRLA batteries should not be stored for more than 6 months at 77º F (25º C) without recharged. The specific gravity or voltage of flooded batteries should be monitored every 4 - 6 weeks and should be given a boost charge when they are at 70% stat of charge (SOC). When batteries are taken out of long storage, it is recommended to recharge before use.

2. Can I use the specific gravities to troubleshoot my battery?
The specific gravities of batteries are an excellent tool to determine the state of charge of batteries and their ability to accept a charge. Unfortunately, the specific gravities can also lead to an erroneous conclusion if we do not specify the conditions under which the measurements were taken. The two major sources of error in measuring specific gravities are lack of temperature compensation and water addition. Since the specific gravities of batteries are affected by temperature, the measurements must be temperature compensated. The best way to compensate for cold temperatures is to subtract four points from your reading for every 10º F (5.5º C) degrees below 80º F (27º C). To compensate for hot temperatures simply add four points from your reading for every 10º F (5.5º C) degrees above 80º F (27º C). Also, the addition of water should only be done once the batteries are fully charged as the electrolyte levels vary as a function of state of charge and are highest once the batteries are fully charged. Please use-distilled water only and note that adding water will lower the specific gravities of your batteries. The specific gravities cannot be used as a reliable source unless we account for the two sources of error mentioned above.

3. Is it normal for my flooded batteries to lose water?
It is completely normal for flooded batteries to lose water. They lose water because of the gassing that they go through with every charge. Gassing is an important part of the recharge process. The gassing allows the electrolyte to mix well and helps the battery get back to a fully charged state at the end of the charge process. Unfortunately, the gassing also causes water to be lost. The addition of water should be only be done once the batteries are fully charged as the electrolyte levels vary as a function of state of charge and are highest once the batteries are fully charged. The correct electrolyte level is about 1/8th of an inch below the bottom of the vent well. Please use-distilled water only.

4. When should I water my flooded batteries?
Water is lost during the charging of flooded batteries. The best time to water your batteries is always at the end of the charge cycle however, if the plates are exposed to air, add just enough water to cover the plates before starting the charge cycle. When the charging process is complete, re-check the electrolyte and top off as needed.

5. How often should I water my flooded batteries?
It is best to check your new batteries regularly as this will give you a good feel for how often your application will require battery watering. WARNING: A brand new battery may have a low electrolyte level. Charge the battery first and then add water if needed. Adding water to a battery before charging may result in overflow of the electrolyte.

6. Can I add de-ionized water to my flooded batteries instead of distilled water?
Yes, de-ionized water can be used of distilled water. However, distilled water is preferred because although de-ionized water has all free ions removed, it may still contain some minerals that may be harmful to the battery. In addition, distilled water is generally more available than de-ionized water.

7. What is the proper electrolyte level?
Liquid levels should be 1/8 inch below the bottom of the vent well (the plastic tube that extends into the battery). The electrolyte level should not drop below the top of the plates. 

 

8. What is the proper torque value for my battery connections?

Terminal Type
Torque (in/lbs)
Torque (N•m)   Terminal Type
Torque (in/lbs)
Torque (N•m)
LT 100 - 120 136 - 162   Wingnut 95 - 105 129 - 142
LPT 95 - 105 129 - 142   Stud 120 - 180 162 - 244
WARNING: Do not over tighten terminals. Doing so can result in post breakage, post meltdown, and fire.


9. What is the life expectancy of my battery?
The life expectancy of batteries in renewable energy applications is a very dynamic and depends on a number of application specific variables. The life expectancy depends on the proper sizing of the battery bank, depth of discharge, type of loads, battery maintenance regime, ambient temperature, and charging algorithm.

10. Can I do a partial replacement of my flooded batteries?
We do not recommend partial battery replacement of flooded battery banks. The behavior of batteries during discharging and charging varies throughout their lifespan and if all the batteries are the same age, than they all will have similar responses. The danger with replacing only one battery is that the older batteries tend to require more charge than newer batteries, and since the new batteries are in the same circuit, they too will be overcharged. There is also the chance that the older batteries will be undercharged since the overall voltage response of all the batteries (old and new) will not be a good representation of either group. The charging system might erroneously think that ALL the batteries have reached the desired voltage and it may stop the charging of the batteries prematurely.

 

Ratings
1. What are the 20-hour and 100-hour rates?
The 100-hour rate is just an index that is used in the battery industry to compare batteries of different types and sizes. The 100-hour rate is the amount of Ahs the battery will deliver during a 100-hour discharge. The capacity of a battery, in Ahs, is a dynamic number that is dependent on the discharge current. For example, a battery that is discharged at 10A will give you more capacity than a battery that is discharged at 100A. With the 100-hr rate, the battery is able to deliver more Ahs than with the 20-hr rate because the 100-hr rate uses a much lower discharge current than the 20-hr rate. Both rates are used as baselines in different parts of the world. Either rate, however, will give you the same view of a battery. A higher capacity battery will have higher 5 and 20 hour rates than a battery with lower capacity.
 

 

Charging
1. 
When do I need to perform an equalization charge?
Equalizing should be performed when a battery is first purchased (called a freshening charge) and on a regular basis as needed. How often this might occur with your battery will vary depending on your application. You will need to monitor your battery voltage and specific gravity to determine when equalization is needed. For example, it is time to equalize if the measured specific gravity values are below manufacturer's recommended values after charging (recommended value for Trojan Deep Cycle batteries is 1.285 +/- .007 at 80º F (27º C)). Equalizing is also required if the specific gravity value of any individual cell varies 30 points or more. In addition, reduced performance can also be an indicator that equalizing is necessary. Equalization should be performed when individual battery voltages in a battery pack range greater than 0.15 volts for 6-volt batteries or 0.30 volts for 12-volt batteries.