Hallo,

sorry for that noob question but
i have a boost gauge where the vacuum part is in inHg, can someone tell me how to calculate it back into mbar or psi?

i've searched around the internet a while but all calculators i found give me strange results when i typ in i.e. -27inHg (i.e. -27inHg -> -0.5220938611 psi)

i had expected that -27inHg is something around 200mbar...

maybe someone can show me where my calculation error is...
Thanks

 

1 inHg = .491 psi. so if you have 27 inHg that equals 13.26 psig. for absolute pressure you would take the atmospheric pressure in your area, usually 14.7psi and subtract that from 13.26psig to get -1.43 psia which is vacuum (negative pressure).

oh and 27 inHg = 914 mbar.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mikey3000 &raquo;</TD></TR><TR><TD CLASS="quote">1 inHg = .491 psi. so if you have 27 inHg that equals 13.26 psig. for absolute pressure you would take the atmospheric pressure in your area, usually 14.7psi and subtract that from 13.26psig to get -1.43 psia which is vacuum (negative pressure).

oh and 27 inHg = 914 mbar. </TD></TR></TABLE>

14.7 is for people that live at sealevel or below from his avatar he lives in frankfurt, germany im guessin so he's got some elevation

 

here is something that i use.
http://joshmadison.com/software/convert/