Kirchhoff's loop rule (otherwise known as Kirchhoff's voltage law (KVL), Kirchhoff's mesh rule, Kirchhoff's second law, or Kirchhoff's second rule) is a rule pertaining to circuits, and is based on the principle of conservation of energy.
ECM stands for Electronically Commutated Motor. Basically, circulator pumps with ECM motors offer intelligent speed control. Speed-controlled pumps automatically adjust their output to changing demand, whether it be due to outside temperature, level of sunlight, overall activity, and other heating sources. The benefit of having a more efficient ECM motor pump is substantial energy savings, which directly relates to cost savings.
A drum pump, also called an oil drum pump or oil barrel pump, is used to remove liquids from barrels, drums, tanks, and intermediate bulk containers (IBCs). Drum pumps consist of an intake tube, a pumping mechanism, an outflow hose, and often a nozzle of some type. Drum pumps come in many forms from the rotary type to a variety of other styles including lever, piston, siphon, double diaphragm, electric, and air. The 55 gallon drum pump is most common, because it is a standard drum size. The intake valve of a 55 gal drum pump is inserted into a bung hole, and the pump sits atop the barrel. The siphon drum pump, lever-action, and rotary drum pump, due to their simplicity, are the most commonly used type of 55 gallon drum pumps. An electric barrel pump reduces the time required to dispense liquids.