Optima Batteries WEB SITE SAYS
DUAL PURPOSE (STARTING & DEEP CYCLE) BATTERIES
MODEL NUMBER YT S 5.5 YT S 4.2 YT U 4.2 YT R 3.7 YT S 2.7 & 2.7 J
YT R 2.7 & 2.7 J
PERFORMANCE
Voltage (V) 12 12 12 12 12
Cold Cranking Amps @ -18°C (A) 975 765 765 660 510
Cranking Amps @ 0°C (A) 1125 870 870 810 625
Reserve Capacity (Minutes) 155 120 120 98 70
Capacity (C/20 Rate) (Ah) 75 55 55 48 41
Internal Resistance (ohms) 0,0025 .0028 .0028 .0030 .0046
PHYSICAL SPECS
Length (mm) 325 254 254 237 237
Width (mm) 165 175 175 172 129
Height (mm) 238 200 200 197 227
Mimimum Weight (kg) 26,5 19,5 19,9 16,6 11,6
Type Post/Terminal 3/8" Stainless SAE SAE & GM SAE SAE & Thin Japanese terminal
BCI Group 31A 34 34/78 35 51 & 51R
Product Spec Sheets
Charging Info
The following charging methods are recommended to insure a long battery life (Always use a voltage regulated charger, with voltage limits set as described below):
All OPTIMA® YellowTop Batteries
These batteries are dual purpose. They are designed for engine start and cyclic applications and for use in vehicles with large accessory loads.
Recommended charging information:
Alternator:
13.65 to 15.0 volts, no amperage limit.
Battery charger:
13.8 to 15.0 volts, 10 amps maximum, 6-12 hours approximate.
Cyclic Applications:
14.7 volts, no current limit as long as battery temperature remains below 50°C (125°F). When current falls below 1 amp, finish with 3 amp constant current for 1 hour for YT S 5,5.and 2 amp constant current for 1 hour for all other types.
Rapid Recharge:
Maximum voltage 15.6 volts (regulated).
Maximum current: No limit as long as temperature <50°C (125°F).
Maximum recharge time: Charge until current drops below 1 amp.
Float charge:
13.2 to 13.8 volts, 1 amp maximum current, time indefinite (at lower voltage).
All limits must be strictly adhered to.
Safety Information:
Always wear safety glasses when working with batteries.
Always use a voltage regulated battery charger with limits set to the above ratings. Overcharging can cause the safety valves to open and battery gasses to escape, resulting in premature failure. These gasses are flammable! You cannot replace water in sealed batteries that have been overcharged. Any battery that becomes very hot or makes a hissing sound while recharging should be disconnected immediately.
Failure to fully charge a battery can result in poor performance and a reduction in capacity