Sima Products STP-1000T Manuale Utente

100 watt 

9 Amps 

5.5 hours 

11 hours 

200 watt 

19 Amps 

2.6 hours 

5.2 hours 

500 watt 

47 Amps 

1 hour 

2 hours 

 
Actual Current Draw 
Approximate 12 volt current draw is the load in watts divided by 10.  Thus a 60 watt light bulb 
plugged into the inverter will cause the inverter to draw 6 amps (60 / 10 = 6) from the 12 volt 
supply. 
 
  
Batteries are rated in several different ways: 

Peak cranking amps - This has little to do with how long an inverter can supply power, so it 

is not a useful number for inverter operation. 

Battery reserve capacity - This number shows how long a battery can supply a given current, 

typically 25 amps, before the battery voltage reaches a low voltage.  Therefore, a battery 
rated at 200 minutes reserve can deliver 25 amps for 200 minutes before it is discharged. 

Ampere-hour capacity - This rating indicates how many amps a battery can deliver over a 

period of time, typically 20 hours. Therefore, a 100 amp-hour battery can deliver 5 amps 
for 20 hours (5 x 20 = 100). 

 
Actual operating time from a battery will depend upon the current draw from the battery.  A 

battery will deliver less total power (energy) as you draw higher amps.  A 100 amp-hour 
battery can deliver 5 amps for 20 hours (100 amp-hours) but it will only deliver 50 amps 
for 1 ½  hours (50 x 1.5 = 75) or 75 amp-hours at the higher rate. 

Also remember, battery life is decreased if the battery is discharged fully.  Lead acid 

batteries have the longest life, if they are kept fully charged. 

POWER Indicator (Green) 
This light will illuminate when the inverter is turned on and is operating normally.  If this light goes 
out the 12 volt power is missing (possible blown fuse).  These fault conditions include output 
overload, output short circuit, low input voltage and over temperature of the unit. This can happen if 
a device has a large turn on surge, if an appliance (like a drill or saw) is stalled or if the inverter does 
not have a supply of cool air.   

 

Fault Indicator (Red) Fault conditions include output overload, output short circuit, low input 
voltage and over temperature of the unit. This can happen if a device has a large turn on surge, if an 
appliance (like a drill or saw) is stalled or if the inverter does not have a supply of cool air.   

 
Fuse Replacement  
If you overload the power inverter, it is possible that the external fuse might blow.  Always determine 
the cause of the fuse blowing and remedy the problem before using the power inverter again. 

page 11