milla-amp readings

passgas55

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ms20 at idle, 1.4 ma
ms20 at trip, 2.0 ma(with relay 26 ma)
single stage 555, 11.4 ma(seems high)
single stage 555 with relay, 24.5ma
Notice that my timer when trip only gives a short pulse, not the 2 sec I was looking for but if I jump out the n.o. contacts on timmer board and remove 12v relay so that now the power to timer is control by n.o. contacts , then I get 2 sec. pickup on 5v relay. This works great because my timmer only use power when the ms20 is in the detect state. I want to remove 12v relay and power up the 555 by using the ms2o direct. Any comments
 

Tinhorn

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passgas55

The current for the MS20 looks about right.  

If you are using 555 timers instead of the TLC 555 timers, then those readings are probably right too, TLC's are "WAYee" more efficient than 555's!   On my timers, I get a current draw, at idle, of 2.14 ma's using a 6v lantern batt ( MS20's and 2 stage timer combined)

with regards to the rest of your post, I kind of got lost      :(

Tinhorn
 
A

Archilochus2

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Hi pg55,
11.4mA seems high even for a pair of the ineffiecient NE555's.  Sounds like you might have chosen low resistor values for your 555 timing - or maybe have some bad timing capacitors. Either one can lead to excessive power consumption.
>>>>>
What you're trying to do with the 555 is referred to as "power-gating"  - temporarily powering up a portion of a circuit only as it is needed.  With the 555 this could be a hit-or-miss design.  When first powered-up, the 555 *usually* generates a spurious pulse due to the ON/OFF switch 'bounce'.  The key word there is usually!!  The 555 does not do it every time!!  So just as Sasquatch is taking a stroll by your camera, that's when it will decide to not work!  You'll have more reliable results using the 555 always powered-up.  You just need to figure out why your 555's are using so much power.
>>>>
For truly low-power timer circuits, use the HCF4047B, HCF4538B, 74HC(T)221, or 74HC(T)123 monostables available special order from RS or from Mouser electronics - http://www.mouser.com   These IC's consume power only when they are generating an output pulse.

Archilochus
 

passgas55

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built another single stage 555 and this one draws only .49 ma and trips out at a little under 2 seconds.
If I want to increase my trip time what resistor/cap do I have to change? Thanks
 

Tinhorn

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The resistor & cap that connects to pin 6 & 7 of the TLC555 or 555 are the timing components.  

It's more energy efficient to have a high "Resistor" value and a Lower Cap value, by high, I mean over 100k ohms, something in the neighborhood of 1M would be nice

Tinhorn
 

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