Electric rain water pump options

When looking at possibilities for electrically-powered pumps, I encountered several options that I want to remember in case I decide to add an electric pump to my rain water system.  There are several types of pumps, but I haven't explored what is presently popular for the actual part which moves water.

What I did take note of is that one type of pump assembly would be convenient for many situations:  A demand pump or on-demand pump combines a pump with a pressure cutoff switch.  The pump will automatically turn off when its output side has more than a certain pressure, such as 30 or 40 PSI (pounds per square inch).  When connected to a hose or watering system, this allows the pump to turn off when water is no longer needed or when the pump is moving water faster than it can drain out.  A diaphragm tank (because there is a flexible diaphragm which uses pressurized air to push water out of the tank) can hold some pressurized water, so a more constant flow of water can be provided.

However, a pressure cutoff switch only controls what is happening on the output side of the pump and does not protect against what is happening on the input side.  A low water cutoff switch or float switch can turn off the pump when the water level in the rain barrel gets too low.  That protects the pump from trying to pump air, or pumping dry.  A float switch can also be used to stop a pump when a destination barrel is full.

Rain gutter and downspout terminology

I had to look up what to call some of the pieces involved with gutters.  From top to bottom, here is a glossary of some terms:

• Rain deflector:  Not actually part of a gutter but rather it is a metal guide which is installed on the roof over a door to guide water sideways and thus reduces water falling over the door.  Often not needed over a gutter system.
• Drip edge flashing: Metal roof edge which extends from under shingles.  Guides water away from edge of shingles.  Might be considered part of the roof.
• Fascia board: Board running along the ends of the rafters at the edge of the roof.  The gutter is often attached to it.
• Splash guard: A baffle which raises the edge of a gutter, to divert the flow of water into the gutter. Often needed at an inside corner due to the water flow from the corresponding trough where two roofs meet.
• Gutter leaf guard: A screen or other device over the gutter to block most leaves from entering the trough.
• Hangers: Brackets that support the gutter.
• Rain gutter, gutter, or eaves trough: The horizontal trough which captures rain water below the edge of the roof.
• Drop out or outlet tube: Connector for the top end of a downspout.  Short tube which is sealed to the edges of a hole in the gutter which has been cut for the tube.
• Leader head, conductor head, or rainhead: A decorative box to collect rain water from gutters and guide it down a downspout.  Used instead of an outlet tube.
• Downspout strainer: A wire mesh or grate at the top of the downspout to block debris from flowing down the downspout.
• Downspout: The vertical tube which carries water downward.
• Downspout strap: Metal straps which hold the downspout against the wall.
• Offset: Elbows used to route a downspout around an obstruction on the wall.
• Downspout diverter: A device to divert water, automatically or manually, between a rainbarrel and downspout.
• Elbow: Often the bottom of a downspout has an elbow which sends the rain away from the building, either away from the wall or to the side (probably toward the corner of the building).  Often a length of downspout, hinged trough, or other device is used to carry the water further from the building.
• Splash block: A concrete pad, masonry, or other device on the ground to protect the ground from the force of water falling from a downspout.