Agitation and sumps 1

[vanskat]

Here is a good one.
Yesterday I was called up on to implement an agitation system inside a sump pit; purpose of which is to create a suspension before the heavy stuff is moved by the sump pump.

I opted to insert a perforated pipe into the pit whose water flow [agitiation]is controlled with a solenoid valve.
The philosophy is that when the control cct is completed the solenoid would kick in for say 20s after which the pump would start.

A simple exercise I thought..however, I was forced to use only {normally open time to close} and {normally closed time to open} relays. Anyway I ended up with 6 relays total for a simple delay.....

 

[jbartos]

Suggestion: Visit

http://www.connex-electronics.com/?url=/html/products/finder_main_select.html

for timers that could potentially combine {normally open time to close} and {normally closed time to open} relays.

 

[busbar]

For standalone control with front-panel indication/adjustment, an old standby is an Eagle Signal HG-series repeat-cycle timer.