Frequently Asked Questions
What is the Crown CR-235 battery?
The Crown CR-235 is a 6VDC deep cycle flooded lead acid battery rated at 235Ah at the 20-hour rate. It is designed for applications requiring repeated charge and discharge cycles, including solar energy storage, backup power, RVs, marine equipment, golf carts, and industrial equipment.
Is the Crown CR-235 a good battery for solar?
Yes. The Crown CR-235 is suitable for off-grid solar and renewable energy systems that use flooded lead acid battery banks. Its 6VDC configuration allows multiple batteries to be connected in series to create higher-voltage battery banks.
How much energy does the Crown CR-235 store?
The Crown CR-235 is rated at 235Ah at the 20-hour rate and 6VDC. Crown lists 1.37 kWh of rated storage at the 20-hour rate. Actual usable energy will depend on discharge rate, temperature, battery age, depth of discharge, and system design.
How many Crown CR-235 batteries are needed for a solar system?
The number required depends on the system voltage, energy demand, desired backup time, and battery-bank design. Common series configurations include:
- Two batteries in series for a 12VDC battery bank
- Four batteries in series for a 24VDC battery bank
- Eight batteries in series for a 48VDC battery bank
Additional series strings can be connected in parallel when more total amp-hour capacity is required. The complete bank should be sized around the system's daily energy use, solar production, inverter requirements, and allowable depth of discharge.
What are the dimensions and weight of the Crown CR-235?
The Crown CR-235 measures 10.25 x 7.06 x 10.94 inches (26.04 x 17.93 x 27.79 cm) and weighs approximately 63 lbs (28.6 kg). Verify available battery-compartment space and terminal clearance before installation.
Charging & Maintenance
How should the Crown CR-235 be charged in a solar system?
Use a solar charge controller configured for flooded lead acid batteries and follow Crown's charging recommendations for the specific application. The charging system should provide the appropriate charging stages and voltage settings for flooded batteries. Proper charging helps prevent chronic undercharging and excessive overcharging.
Does the Crown CR-235 require watering?
Yes. The Crown CR-235 is a flooded lead acid battery and requires periodic electrolyte inspection and watering. Use distilled or de-mineralized water and maintain the electrolyte at the proper level. Follow the manufacturer's maintenance instructions when servicing the battery.
How often should the Crown CR-235 water level be checked?
The inspection interval depends on charging practices, cycling frequency, temperature, battery age, and operating conditions. Regular inspection is important for flooded batteries, and new batteries can be checked at approximately two-week intervals to establish a maintenance baseline. Inspection may need to become more frequent as the battery ages or operating conditions change.
Can I use tap water in the Crown CR-235?
No. Use distilled or de-mineralized water. Minerals and impurities in tap water can contaminate the electrolyte and negatively affect battery performance and service life.
Does the Crown CR-235 need ventilation?
Yes. Flooded lead acid batteries can release hydrogen gas during charging. The Crown CR-235 should be installed upright in a properly ventilated location and kept away from sparks, flames, cigarettes, and other ignition sources.
Crown Battery Comparison
What is the difference between the Crown CR-235 and Crown CR-205?
The Crown CR-205 and CR-235 are both 6VDC GC2 deep cycle flooded lead acid batteries. The Crown CR-235 provides 235Ah at the 20-hour rate compared with 205Ah for the Crown CR-205, giving the CR-235 more rated energy storage. Both have the same listed dimensions, while the CR-235 is heavier. The Crown CR-235 is better suited when maximizing capacity within the available GC2 footprint is more important than minimizing battery weight.
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Specification
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CR-205
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CR-235
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Voltage
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6VDC
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6VDC
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Capacity (20 Hr)
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205Ah
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235Ah
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Capacity (5 Hr)
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170Ah
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185Ah
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Storage kWh (20 Hr)
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1.19 kWh
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1.37 kWh
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Reserve Capacity
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105 min @ 75A
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122 min @ 75A
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Dimensions
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10.25 x 7.06 x 10.94 in (26.04 x 17.93 x 27.79 cm)
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10.25 x 7.06 x 10.94 in (26.04 x 17.93 x 27.79 cm)
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Weight
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56 lbs (25.4 kg)
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63 lbs (28.6 kg)
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Terminal Type
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Dual post/Stud combination
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Dual post/Stud combination
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What is the difference between the Crown CR-235 and Crown CR-220?
The Crown CR-220 and CR-235 are both 6VDC GC2 deep cycle flooded lead acid batteries with the same listed dimensions. The Crown CR-235 provides 235Ah at the 20-hour rate compared with 220Ah for the Crown CR-220 and offers 1.37 kWh of rated storage compared with 1.28 kWh. The Crown CR-235 is slightly heavier but provides more capacity for systems where additional energy storage is the priority.
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Specification
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CR-220
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CR-235
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Voltage
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6VDC
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6VDC
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Capacity (20 Hr)
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220Ah
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235Ah
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Capacity (5 Hr)
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180Ah
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185Ah
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Storage kWh (20 Hr)
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1.28 kWh
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1.37 kWh
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Reserve Capacity
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110 min @ 75A
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122 min @ 75A
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Dimensions
|
10.25 x 7.06 x 10.94 in (26.04 x 17.93 x 27.79 cm)
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10.25 x 7.06 x 10.94 in (26.04 x 17.93 x 27.79 cm)
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Weight
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60 lbs (27.2 kg)
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63 lbs (28.6 kg)
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Terminal Type
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Dual post/Stud combination
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Dual post/Stud combination
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Solar Application & Battery Life
How deeply should I discharge the Crown CR-235 in a solar system?
For solar applications, avoiding unnecessary deep discharges can help extend flooded lead acid battery life. A properly sized battery bank should provide enough capacity for normal loads without routinely reaching a very low state of charge. Shallower cycling generally places less stress on the battery than repeated full discharges.
How long will a Crown CR-235 last in a solar system?
There is no single service-life figure that applies to every Crown CR-235 installation. Actual life depends on depth of discharge, cycling frequency, charging, temperature, watering, storage, and maintenance. Keeping the battery properly charged and avoiding unnecessary deep discharge can help maximize its service life.
Can the Crown CR-235 be installed on its side?
No. The Crown CR-235 is a flooded lead acid battery containing liquid electrolyte and should be installed upright. Upright installation also allows the battery to be inspected and maintained correctly.
Is the Crown CR-235 maintenance free?
No. Because it is a flooded lead acid battery, the Crown CR-235 requires regular maintenance, including electrolyte inspection and watering. If low maintenance is a priority, another battery technology may be more appropriate, depending on the solar system's charging equipment, space, capacity requirements, and budget.
What should I check if my Crown CR-235 is not performing as expected?
Check the solar charge controller settings, battery connections, terminal condition, electrolyte level, and overall battery condition. Make sure the battery is receiving an appropriate charge before evaluating its capacity. Poor performance may result from undercharging, excessive discharge, sulfation, low electrolyte, high temperatures, poor connections, or normal battery aging.
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