I'm trying to decide on a best option to control a water pump in my irrigation system. I need to be able to set on time to about 1 minute and off time to about 5 minutes or so. Most cheap timers you get from the shops can only have a few on/off settings or can be set to only 15 minute periods so that's not an option.
I've made a similar circuit using 555 timers and a relay before, but if possible I'd like to avoid using external power supply or batteries and it needs to be super reliable because it needs to be running 24/7 year round without failing.
I've been looking at timer relays such as this: **broken link removed**
If I understand the datasheet correctly it requires no external power supply when connected to the mains and can be set from 0.1s to 100h periods which is good. The only issue is it costs $150. Does anyone have an experience with this type of timers? How well do they work and are they really worth all the extra money when compared to a 555 timer circuit?
Any opinion is appreciated.
I've made a similar circuit using 555 timers and a relay before, but if possible I'd like to avoid using external power supply or batteries and it needs to be super reliable because it needs to be running 24/7 year round without failing.
I've been looking at timer relays such as this: **broken link removed**
If I understand the datasheet correctly it requires no external power supply when connected to the mains and can be set from 0.1s to 100h periods which is good. The only issue is it costs $150. Does anyone have an experience with this type of timers? How well do they work and are they really worth all the extra money when compared to a 555 timer circuit?
Any opinion is appreciated.