Installation Manual

Page 56

Appendix D – Inverter/Charger Terminology

Locked Rotor Amps – The current drawn by an electric motor with the shaft or rotor stopped

and locked in position. This can be used to determine if an inverter has enough surge current to

start a motor. If the inverter is capable of producing more amperage than the locked rotor amps

rating of a motor, it will most likely start the motor easily.

NEC (National Electric Code) – The guidelines and acceptable practices for electrical installations

in the USA.

Off Grid – Not connected to public power in any way.

Pass Through Current – The amount of current the inverter can safely pass directly from the

AC input to the AC output.

Photovoltaic (PV) – Solar powered.

Resistance (Ohms) – Slows the electrical ﬂ ow of Direct Current (DC)

RMS (Root Mean Square) – A measure of AC voltage that provides the equivalent heating

value across a resistor as would a DC source of the same voltage.

Sellback, or Selling Back To The Grid or Utility-Interactive – Some inverters have the

capability to take energy stored in batteries, or from solar panels, and put it back into the utility

grid. The local public utility company can compensate you for using this energy.

Shorepower – The process of providing shore-side electrical power to a boat while its main

and auxiliary engines are turned off. The source for shorepower may be grid power from an

electric utility company, or from an external remote generator.

Stacking:

• Series – Two inverters operating together to produce twice the power and voltage of a

single inverter. Required when operating 240 VAC loads and separate 120 VAC loads from

either inverter.

• Parallel – Two inverters operating together to provide twice the continuous capacity on a

single output circuit. Required when a single load is too large for one inverter.

Stratiﬁ cation – Over time, a battery’s electrolyte (liquid) tends to separate. The electrolyte at

the top of the battery becomes watery while at the bottom it becomes more acidic. This effect is

corrosive to the plates.

Sulfating – As a battery discharges, its plates become covered with lead sulfate. During

recharging, the lead sulfate leaves the plates and recombines with the electrolyte. If the lead

sulfate remains on the plates for an extended period of time (over two months), it hardens, and

recharging will not remove it. This reduces the effective plate area and the battery’s capacity.

Temperature Compensation – Peak available battery voltage is temperature dependent. As

ambient temperatures fall, the proper voltage for each charge stage needs to be increased. A

Battery Temperature Sensor (BTS) automatically re-scales charge-voltage settings to compensate

for ambient temperatures.

Voltage – The pressure that causes electrical ﬂ ow in a circuit.

Watts – Measure of power output or utilization. Watts = Volts x Amps.