Temperature sensitivity with electronic scales
Moderators: deerhunter338mag, Vaughan, stokesrj
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- Meister der jagd
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- Location: Australia
Temperature sensitivity with electronic scales
Interested in other people experience in this area. As my man cave is a little way off, a bench in my shed is the temporary set up. When the sun is shinning the internal temp in the shed is a few degrees warmer and rather pleasant ( its winter here at the moment with daytime temps ~ 8 to 11c). But when the sun goes down it cools down and that’s when the fun starts.
Between 10 am and 3 pm, the scale is spot on as far as I can tell as my calibration weight comes back with the same reading post warm up. From 4pm, when the sun goes down the calibration weight reads 0.3 grains lighter. I have tried this three times and the same result on each occasion. I have even left the unit on for more than an hour before this test and the same result.
Again just interested in other people’s experience in this regard.
Cheers
Between 10 am and 3 pm, the scale is spot on as far as I can tell as my calibration weight comes back with the same reading post warm up. From 4pm, when the sun goes down the calibration weight reads 0.3 grains lighter. I have tried this three times and the same result on each occasion. I have even left the unit on for more than an hour before this test and the same result.
Again just interested in other people’s experience in this regard.
Cheers
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Re: Temperature sensitivity with electronic scales
Better take it inside and reload at the dining table.
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- Meister der jagd
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Re: Temperature sensitivity with electronic scales
A for effort advice but suspect better half may have a thing or two to say about such an option
- stokesrj
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Re: Temperature sensitivity with electronic scales
I haven't seen any problems with temperature sensitivity with my RCBS Chargemaster but my temperatures are more controlled than yours. I have seen issues from the line voltage and frequency instabilities. I have a whole house back-up generator that automatically comes on when the power goes out. I've seen that cause similar shifts to what you are seeing. But I'm thinking you really need to work on managing your wife. Good luck with that.
Robert J Stokes
- slugslinger
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Re: Temperature sensitivity with electronic scales
Oscar,
Your observation is not unreasonable. The heart of these devices is a load cell - a load cell is a transducer that is used to create an electrical signal whose magnitude is directly proportional to the force being measured. Since most any electro-mechanical devices can be affected by temperature, it makes sense. The other variable is powering on your device - when you power it on, the electronics and the load cell requires time to "warm up". I leave my RCBS ChargeMaster powered on most of the time unless I'm not going to use it for over week or so. A longer shot is a phenomenon known as diurnal change - Daily variations in the geomagnetic field. This has also been known to affect the sensitivity of electronics and things like radio reception.
Sorry if that's too much info - you "woke up" the retired engineer!
Regards,
Dave
Your observation is not unreasonable. The heart of these devices is a load cell - a load cell is a transducer that is used to create an electrical signal whose magnitude is directly proportional to the force being measured. Since most any electro-mechanical devices can be affected by temperature, it makes sense. The other variable is powering on your device - when you power it on, the electronics and the load cell requires time to "warm up". I leave my RCBS ChargeMaster powered on most of the time unless I'm not going to use it for over week or so. A longer shot is a phenomenon known as diurnal change - Daily variations in the geomagnetic field. This has also been known to affect the sensitivity of electronics and things like radio reception.
Sorry if that's too much info - you "woke up" the retired engineer!
Regards,
Dave
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- deerhunter338mag
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Re: Temperature sensitivity with electronic scales
Best advice you can have. This is where I do all my powder loading, then I go out to the shed to seat them all. Temp is always about the same. Don’t know if it makes any difference but my loads always shoot the same. My RCBS chargemaster is always stored in the house as I’ve seen a few that have been left in the sheds over the colder months that have become targets. Stick to doing everything the same to keep consistency going.
Measure it, when it’s on the deck
- Ringo
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Re: Temperature sensitivity with electronic scales
I've noticed this with both my expensive and inexpensive scales. My solution is to recalibrate when I see any drift. When I take the pan off the scale, there's a number I expect to see (the negative value of the weight of the pan). When it isn't exactly what it should be, I recalibrate.
I've also used a check weight that is near to the charge weight I'm loading. Dropping it onto the pan from time to time provides extra confidence. I haven't done this as much as I've learned to trust the scales.
I've also used a check weight that is near to the charge weight I'm loading. Dropping it onto the pan from time to time provides extra confidence. I haven't done this as much as I've learned to trust the scales.
Ringo, formerly rodell
"Imagine how stupid the average person is, and then think that half of the people are stupider than that". - George Carlin
"Imagine how stupid the average person is, and then think that half of the people are stupider than that". - George Carlin
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Re: Temperature sensitivity with electronic scales
The calibration weight, is it 50 grams? 0.3gr on 50 grams isn’t anything to worry about.
Try it with a lighter weight, maybe a 40gr bullet or something.
Try it with a lighter weight, maybe a 40gr bullet or something.
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- Meister der jagd
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Re: Temperature sensitivity with electronic scales
I use two calibration weights. The 50 gram it comes with and a selected 160 gn projectile.
I agree that having a more constant temperature is better which is why the man cave is my next project. Essentially I will be building a room inside the back of the shed, lined with gyprock which will stabilise the temperate in the room...or should I say slow down the change.
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Re: Temperature sensitivity with electronic scales
I tend to reload with a pair of halogen flood lights next to the bench. They not only provide a good light source but a constant radiant heat source when reloading that takes the edge off when it's cold. You may find it flattens out your temperature variability when reloading.
Oscar wrote: ↑Fri Aug 17, 2018 1:58 am Interested in other people experience in this area. As my man cave is a little way off, a bench in my shed is the temporary set up. When the sun is shinning the internal temp in the shed is a few degrees warmer and rather pleasant ( its winter here at the moment with daytime temps ~ 8 to 11c). But when the sun goes down it cools down and that’s when the fun starts.
Between 10 am and 3 pm, the scale is spot on as far as I can tell as my calibration weight comes back with the same reading post warm up. From 4pm, when the sun goes down the calibration weight reads 0.3 grains lighter. I have tried this three times and the same result on each occasion. I have even left the unit on for more than an hour before this test and the same result.
Again just interested in other people’s experience in this regard.
Cheers