My power supply is built in this way: 220v ac (the same that power the pumps) -> 220/15+15 transformer, 2 diodes for rectifing, a 220 uF electrolitic capacitor, a 7812 for 12v, another 220 uf cap and finally a 7805 for logic. With the 7812 I have a 12 v 7A battery for backup. On Wed, Mar 17, 2010 at 8:24 AM, Alan B Pearce wrote: >> I have a circuit where I have a pic16f877 that commands four water pumps. >> The connections between the pic and the pumps is made this way: >> PIC -> 5k6 resistor -> Bc337 transistor -> relay -> contactor -> pump >> I start the pumps in secuence and when a presure sensor signals, I shut >> down >> every pump one by one. >> When the last pump stops, the pic resets, and it should not. > > How are you getting the power for the PIC? It could be that a power spike > due to the pump turning off resets the PIC. > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- Matias Vidoni eMail: matiasvidoni@mvcom.com.ar MSN Messenger: matiasvidoni@mvcom.com.ar Skype: matiasvidoni WWW: http://www.matiasvidoni.com.ar Google Talk: matiasvidoni@gmail.com -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist