Resistance standard
I investigated this and both NIST (NBS) and NPL use refined mineral oil A.K.A liquid paraffin for room to medium temeperature baths. This is a food/pharmaceutical grade oil. It is a clear white oil, pretty much non-toxic and no disposal concerns. The materials in older standards will have been intened for immersion in this, not modern synthetic oils. A commercial food or confectionery supply house should be able to supply larger quantities at resonable cost.
Robert G8RPI.
--- On Mon, 22/8/11, Mitch Van Ochten mitch@vincentelectronics.com wrote:
From: Mitch Van Ochten mitch@vincentelectronics.com
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement" volt-nuts@febo.com
Date: Monday, 22 August, 2011, 23:50
Hi Rob,
ESI recommended "Drakeol 9 LT mineral oil" in their literature which I couldn't find in small
quantities. I investigated a synthetic oil replacement called SpectraSyn PAO and Exxon offered
to send a sample. After checking with a chemist at work I decided not to.
He said over many years of immersion the "long chain parrafin" as Mike mentioned would be the best, and
less likely to deteriorate the insulation than the synthetic replacement.
I have attached a chart he sent me for the group's observation.
Mitch
----- Original Message ----- From: "Rob Klein" rob.klein@smalldesign.nl
To: "Discussion of precise voltage measurement" volt-nuts@febo.com
Sent: Monday, August 22, 2011 8:10 AM
Subject: Re: [volt-nuts] Resistance standard
Hi Mike and Charlie,
For the oil, I have decided on the stuff that is sold locally as "sewing machine oil". This is a highly refined light mineral oil, guaranteed to be acid free.
As explained in my previous message, things haven't been progressing over the last 18 months, but I'm going to pick it up again soon, so stay tuned.
Best regards,
Rob.
Op 23-7-2011 19:14, Charles Black schreef:
Hi,
The traditional oil for standard resistors and oil baths is Mineral Oil. The cheapest source of Mineral Oil USP for small quantities is out local grocery store at about $5.50 per pint. It is a highly purified paraffin oil. If you need a large quantity then check out Exxon Marcol 72 which is available for about $12 per liter from Measurements International. I am trying to find a much better price since I could potentially use 157 liters if I am able to get a used bath that I know of.
Charlie
On 7/23/2011 3:03 AM, m k wrote:
Hi,
I only recently joined this group, but in answer to rob, the best oil would be a long chain parrafin, can be purchased for vacuum pumps, also a solid encapsulation will shift as it ages, and that would put strain on the resistors, so they would need an initial wrap in a silicone perhaps? definately a very compliant cover of some sort to isolate the strain.
Mike
PS I am shortly going to set up some LTZ's for a small family of references to age and compare. Doing the sums a difference measure between each one and graphed will tell me which ones are the most stable, then after a year or so splash out and get one calibrated against a known source.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
-----Inline Attachment Follows-----
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
I have an L&N 10k oil-bath standard which is filled with something that
smells a lot like kerosene.
The stuff I am going to use is not a synthetic oil but, as I mentioned
earlier, a mineral oil. According to the manufacturer, it is made up of
"paraffinic and cyclo-paraffinic hydro-carbons"
Rob.
Op 23-8-2011 8:33, Robert Atkinson schreef:
I investigated this and both NIST (NBS) and NPL use refined mineral oil A.K.A liquid paraffin for room to medium temeperature baths. This is a food/pharmaceutical grade oil. It is a clear white oil, pretty much non-toxic and no disposal concerns. The materials in older standards will have been intened for immersion in this, not modern synthetic oils. A commercial food or confectionery supply house should be able to supply larger quantities at resonable cost.
Robert G8RPI.
--- On Mon, 22/8/11, Mitch Van Ochtenmitch@vincentelectronics.com wrote:
From: Mitch Van Ochtenmitch@vincentelectronics.com
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Date: Monday, 22 August, 2011, 23:50
Hi Rob,
ESI recommended "Drakeol 9 LT mineral oil" in their literature which I couldn't find in small
quantities. I investigated a synthetic oil replacement called SpectraSyn PAO and Exxon offered
to send a sample. After checking with a chemist at work I decided not to.
He said over many years of immersion the "long chain parrafin" as Mike mentioned would be the best, and
less likely to deteriorate the insulation than the synthetic replacement.
I have attached a chart he sent me for the group's observation.
Mitch
----- Original Message ----- From: "Rob Klein"rob.klein@smalldesign.nl
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Sent: Monday, August 22, 2011 8:10 AM
Subject: Re: [volt-nuts] Resistance standard
Hi Mike and Charlie,
For the oil, I have decided on the stuff that is sold locally as "sewing machine oil". This is a highly refined light mineral oil, guaranteed to be acid free.
As explained in my previous message, things haven't been progressing over the last 18 months, but I'm going to pick it up again soon, so stay tuned.
Best regards,
Rob.
Op 23-7-2011 19:14, Charles Black schreef:
Hi,
The traditional oil for standard resistors and oil baths is Mineral Oil. The cheapest source of Mineral Oil USP for small quantities is out local grocery store at about $5.50 per pint. It is a highly purified paraffin oil. If you need a large quantity then check out Exxon Marcol 72 which is available for about $12 per liter from Measurements International. I am trying to find a much better price since I could potentially use 157 liters if I am able to get a used bath that I know of.
Charlie
On 7/23/2011 3:03 AM, m k wrote:
Hi,
I only recently joined this group, but in answer to rob, the best oil would be a long chain parrafin, can be purchased for vacuum pumps, also a solid encapsulation will shift as it ages, and that would put strain on the resistors, so they would need an initial wrap in a silicone perhaps? definately a very compliant cover of some sort to isolate the strain.
Mike
PS I am shortly going to set up some LTZ's for a small family of references to age and compare. Doing the sums a difference measure between each one and graphed will tell me which ones are the most stable, then after a year or so splash out and get one calibrated against a known source.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
-----Inline Attachment Follows-----
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
--
Small Design
Zuiddijk 354
1505 HD Zaandam
The Netherlands
tel. +31 (0)75 77 11 740
fax. +31 (0)75 77 11 742
e-mail: rob.klein@smalldesign.nl
Hi,
The troublesome part is the "cyclo-parraffinic" oil, that means you do have some benzene rings in there that may react or dissolve other plastic bits in the bath.Medicinal paraffin is suitable, but possibly a higher viscosity than you want. "Natural gasoline" is fairly parraffinic and does smell a bit like kerosene, so it could be that?
Date: Tue, 23 Aug 2011 10:47:21 +0200
From: rob.klein@smalldesign.nl
To: volt-nuts@febo.com
Subject: Re: [volt-nuts] Resistance standard
I have an L&N 10k oil-bath standard which is filled with something that
smells a lot like kerosene.
The stuff I am going to use is not a synthetic oil but, as I mentioned
earlier, a mineral oil. According to the manufacturer, it is made up of
"paraffinic and cyclo-paraffinic hydro-carbons"
Rob.
Op 23-8-2011 8:33, Robert Atkinson schreef:
I investigated this and both NIST (NBS) and NPL use refined mineral oil A.K.A liquid paraffin for room to medium temeperature baths. This is a food/pharmaceutical grade oil. It is a clear white oil, pretty much non-toxic and no disposal concerns. The materials in older standards will have been intened for immersion in this, not modern synthetic oils. A commercial food or confectionery supply house should be able to supply larger quantities at resonable cost.
Robert G8RPI.
--- On Mon, 22/8/11, Mitch Van Ochtenmitch@vincentelectronics.com wrote:
From: Mitch Van Ochtenmitch@vincentelectronics.com
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Date: Monday, 22 August, 2011, 23:50
Hi Rob,
ESI recommended "Drakeol 9 LT mineral oil" in their literature which I couldn't find in small
quantities. I investigated a synthetic oil replacement called SpectraSyn PAO and Exxon offered
to send a sample. After checking with a chemist at work I decided not to.
He said over many years of immersion the "long chain parrafin" as Mike mentioned would be the best, and
less likely to deteriorate the insulation than the synthetic replacement.
I have attached a chart he sent me for the group's observation.
Mitch
----- Original Message ----- From: "Rob Klein"rob.klein@smalldesign.nl
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Sent: Monday, August 22, 2011 8:10 AM
Subject: Re: [volt-nuts] Resistance standard
Hi Mike and Charlie,
For the oil, I have decided on the stuff that is sold locally as "sewing machine oil". This is a highly refined light mineral oil, guaranteed to be acid free.
As explained in my previous message, things haven't been progressing over the last 18 months, but I'm going to pick it up again soon, so stay tuned.
Best regards,
Rob.
Op 23-7-2011 19:14, Charles Black schreef:
Hi,
The traditional oil for standard resistors and oil baths is Mineral Oil. The cheapest source of Mineral Oil USP for small quantities is out local grocery store at about $5.50 per pint. It is a highly purified paraffin oil. If you need a large quantity then check out Exxon Marcol 72 which is available for about $12 per liter from Measurements International. I am trying to find a much better price since I could potentially use 157 liters if I am able to get a used bath that I know of.
Charlie
On 7/23/2011 3:03 AM, m k wrote:
Hi,
I only recently joined this group, but in answer to rob, the best oil would be a long chain parrafin, can be purchased for vacuum pumps, also a solid encapsulation will shift as it ages, and that would put strain on the resistors, so they would need an initial wrap in a silicone perhaps? definately a very compliant cover of some sort to isolate the strain.
Mike
PS I am shortly going to set up some LTZ's for a small family of references to age and compare. Doing the sums a difference measure between each one and graphed will tell me which ones are the most stable, then after a year or so splash out and get one calibrated against a known source.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
-----Inline Attachment Follows-----
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
--
Small Design
Zuiddijk 354
1505 HD Zaandam
The Netherlands
tel. +31 (0)75 77 11 740
fax. +31 (0)75 77 11 742
e-mail: rob.klein@smalldesign.nl
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
Hi,
I found a US and a UK supplier
Clarion 90 $88 5 Gal
http://www.clarionlubricants.com/do/product/FOOD_GRADE/633507009
UK
EXOL Medic 15 £96 25 litres
http://www.lubetechshop.co.uk/index.php?cPath=25_49
The US suppler has more datasheets and a selection of viscosity grades available.
Another source that I think has been mentioned before is animal / vet suppliers.
Robert G8RPI.
--- On Tue, 23/8/11, Rob Klein rob.klein@smalldesign.nl wrote:
From: Rob Klein rob.klein@smalldesign.nl
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement" volt-nuts@febo.com
Date: Tuesday, 23 August, 2011, 9:47
I have an L&N 10k oil-bath standard which is filled with something that
smells a lot like kerosene.
The stuff I am going to use is not a synthetic oil but, as I mentioned
earlier, a mineral oil. According to the manufacturer, it is made up of
"paraffinic and cyclo-paraffinic hydro-carbons"
Rob.
Op 23-8-2011 8:33, Robert Atkinson schreef:
I investigated this and both NIST (NBS) and NPL use refined mineral oil A.K.A liquid paraffin for room to medium temeperature baths. This is a food/pharmaceutical grade oil. It is a clear white oil, pretty much non-toxic and no disposal concerns. The materials in older standards will have been intened for immersion in this, not modern synthetic oils. A commercial food or confectionery supply house should be able to supply larger quantities at resonable cost.
Robert G8RPI.
--- On Mon, 22/8/11, Mitch Van Ochtenmitch@vincentelectronics.com wrote:
From: Mitch Van Ochtenmitch@vincentelectronics.com
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Date: Monday, 22 August, 2011, 23:50
Hi Rob,
ESI recommended "Drakeol 9 LT mineral oil" in their literature which I couldn't find in small
quantities. I investigated a synthetic oil replacement called SpectraSyn PAO and Exxon offered
to send a sample. After checking with a chemist at work I decided not to.
He said over many years of immersion the "long chain parrafin" as Mike mentioned would be the best, and
less likely to deteriorate the insulation than the synthetic replacement.
I have attached a chart he sent me for the group's observation.
Mitch
----- Original Message ----- From: "Rob Klein"rob.klein@smalldesign.nl
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Sent: Monday, August 22, 2011 8:10 AM
Subject: Re: [volt-nuts] Resistance standard
Hi Mike and Charlie,
For the oil, I have decided on the stuff that is sold locally as "sewing machine oil". This is a highly refined light mineral oil, guaranteed to be acid free.
As explained in my previous message, things haven't been progressing over the last 18 months, but I'm going to pick it up again soon, so stay tuned.
Best regards,
Rob.
Op 23-7-2011 19:14, Charles Black schreef:
Hi,
The traditional oil for standard resistors and oil baths is Mineral Oil. The cheapest source of Mineral Oil USP for small quantities is out local grocery store at about $5.50 per pint. It is a highly purified paraffin oil. If you need a large quantity then check out Exxon Marcol 72 which is available for about $12 per liter from Measurements International. I am trying to find a much better price since I could potentially use 157 liters if I am able to get a used bath that I know of.
Charlie
On 7/23/2011 3:03 AM, m k wrote:
Hi,
I only recently joined this group, but in answer to rob, the best oil would be a long chain parrafin, can be purchased for vacuum pumps, also a solid encapsulation will shift as it ages, and that would put strain on the resistors, so they would need an initial wrap in a silicone perhaps? definately a very compliant cover of some sort to isolate the strain.
Mike
PS I am shortly going to set up some LTZ's for a small family of references to age and compare. Doing the sums a difference measure between each one and graphed will tell me which ones are the most stable, then after a year or so splash out and get one calibrated against a known source.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
-----Inline Attachment Follows-----
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
--
Small Design
Zuiddijk 354
1505 HD Zaandam
The Netherlands
tel. +31 (0)75 77 11 740
fax. +31 (0)75 77 11 742
e-mail: rob.klein@smalldesign.nl
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
Hi,
Well I had a look at both those sites, this tells you about the oil:http://docs.clarionlubricants.com/msds_pi/C10107.pdfIt is certainly parraffinic in nature, as the high pressure hydrotreatment would get rid of any double bonds ( think ethylene etc )The vitamin e treatment may lower the conductivity a bit? but most likely not enough to be of concern.That page also leads me to think that the UK suppliers medic.15 is the same as the clarion 90. the 188 Centigrade flash point is plenty high enough for lab equipment usage. The medic.68/Clarion 350 would be quite syrupy and probably have too low a thermal conductivity as a consequence?
Date: Tue, 23 Aug 2011 12:36:38 +0100
From: robert8rpi@yahoo.co.uk
To: volt-nuts@febo.com
Subject: Re: [volt-nuts] Resistance standard
Hi,
I found a US and a UK supplier
Clarion 90 $88 5 Gal
http://www.clarionlubricants.com/do/product/FOOD_GRADE/633507009
UK
EXOL Medic 15 £96 25 litres
http://www.lubetechshop.co.uk/index.php?cPath=25_49
The US suppler has more datasheets and a selection of viscosity grades available.
Another source that I think has been mentioned before is animal / vet suppliers.
Robert G8RPI.
--- On Tue, 23/8/11, Rob Klein rob.klein@smalldesign.nl wrote:
From: Rob Klein rob.klein@smalldesign.nl
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement" volt-nuts@febo.com
Date: Tuesday, 23 August, 2011, 9:47
I have an L&N 10k oil-bath standard which is filled with something that
smells a lot like kerosene.
The stuff I am going to use is not a synthetic oil but, as I mentioned
earlier, a mineral oil. According to the manufacturer, it is made up of
"paraffinic and cyclo-paraffinic hydro-carbons"
Rob.
Op 23-8-2011 8:33, Robert Atkinson schreef:
I investigated this and both NIST (NBS) and NPL use refined mineral oil A.K.A liquid paraffin for room to medium temeperature baths. This is a food/pharmaceutical grade oil. It is a clear white oil, pretty much non-toxic and no disposal concerns. The materials in older standards will have been intened for immersion in this, not modern synthetic oils. A commercial food or confectionery supply house should be able to supply larger quantities at resonable cost.
Robert G8RPI.
--- On Mon, 22/8/11, Mitch Van Ochtenmitch@vincentelectronics.com wrote:
From: Mitch Van Ochtenmitch@vincentelectronics.com
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Date: Monday, 22 August, 2011, 23:50
Hi Rob,
ESI recommended "Drakeol 9 LT mineral oil" in their literature which I couldn't find in small
quantities. I investigated a synthetic oil replacement called SpectraSyn PAO and Exxon offered
to send a sample. After checking with a chemist at work I decided not to.
He said over many years of immersion the "long chain parrafin" as Mike mentioned would be the best, and
less likely to deteriorate the insulation than the synthetic replacement.
I have attached a chart he sent me for the group's observation.
Mitch
----- Original Message ----- From: "Rob Klein"rob.klein@smalldesign.nl
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Sent: Monday, August 22, 2011 8:10 AM
Subject: Re: [volt-nuts] Resistance standard
Hi Mike and Charlie,
For the oil, I have decided on the stuff that is sold locally as "sewing machine oil". This is a highly refined light mineral oil, guaranteed to be acid free.
As explained in my previous message, things haven't been progressing over the last 18 months, but I'm going to pick it up again soon, so stay tuned.
Best regards,
Rob.
Op 23-7-2011 19:14, Charles Black schreef:
Hi,
The traditional oil for standard resistors and oil baths is Mineral Oil. The cheapest source of Mineral Oil USP for small quantities is out local grocery store at about $5.50 per pint. It is a highly purified paraffin oil. If you need a large quantity then check out Exxon Marcol 72 which is available for about $12 per liter from Measurements International. I am trying to find a much better price since I could potentially use 157 liters if I am able to get a used bath that I know of.
Charlie
On 7/23/2011 3:03 AM, m k wrote:
Hi,
I only recently joined this group, but in answer to rob, the best oil would be a long chain parrafin, can be purchased for vacuum pumps, also a solid encapsulation will shift as it ages, and that would put strain on the resistors, so they would need an initial wrap in a silicone perhaps? definately a very compliant cover of some sort to isolate the strain.
Mike
PS I am shortly going to set up some LTZ's for a small family of references to age and compare. Doing the sums a difference measure between each one and graphed will tell me which ones are the most stable, then after a year or so splash out and get one calibrated against a known source.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
-----Inline Attachment Follows-----
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
--
Small Design
Zuiddijk 354
1505 HD Zaandam
The Netherlands
tel. +31 (0)75 77 11 740
fax. +31 (0)75 77 11 742
e-mail: rob.klein@smalldesign.nl
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
You can buy NuJol at any drug store. Look in the laxative area. It's so
oure, people drink it.
-John
==================
I investigated this and both NIST (NBS) and NPL use refined mineral oil
A.K.A liquid paraffin for room to medium temeperature baths. This is a
food/pharmaceutical grade oil. It is a clear white oil, pretty much
non-toxic and no disposal concerns. The materials in older standards will
have been intened for immersion in this, not modern synthetic oils. A
commercial food or confectionery supply house should be able to supply
larger quantities at resonable cost.
Robert G8RPI.
--- On Mon, 22/8/11, Mitch Van Ochten mitch@vincentelectronics.com
wrote:
From: Mitch Van Ochten mitch@vincentelectronics.com
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement" volt-nuts@febo.com
Date: Monday, 22 August, 2011, 23:50
Hi Rob,
ESI recommended "Drakeol 9 LT mineral oil" in their literature which I
couldn't find in small
quantities. I investigated a synthetic oil replacement called SpectraSyn
PAO and Exxon offered
to send a sample. After checking with a chemist at work I decided not to.
He said over many years of immersion the "long chain parrafin" as Mike
mentioned would be the best, and
less likely to deteriorate the insulation than the synthetic replacement.
I have attached a chart he sent me for the group's observation.
Mitch
----- Original Message ----- From: "Rob Klein" rob.klein@smalldesign.nl
To: "Discussion of precise voltage measurement" volt-nuts@febo.com
Sent: Monday, August 22, 2011 8:10 AM
Subject: Re: [volt-nuts] Resistance standard
Hi Mike and Charlie,
For the oil, I have decided on the stuff that is sold locally as "sewing
machine oil". This is a highly refined light mineral oil, guaranteed to
be acid free.
As explained in my previous message, things haven't been progressing
over the last 18 months, but I'm going to pick it up again soon, so stay
tuned.
Best regards,
Rob.
Op 23-7-2011 19:14, Charles Black schreef:
Hi,
The traditional oil for standard resistors and oil baths is Mineral
Oil. The cheapest source of Mineral Oil USP for small quantities is
out local grocery store at about $5.50 per pint. It is a highly
purified paraffin oil. If you need a large quantity then check out
Exxon Marcol 72 which is available for about $12 per liter from
Measurements International. I am trying to find a much better price
since I could potentially use 157 liters if I am able to get a used
bath that I know of.
Charlie
On 7/23/2011 3:03 AM, m k wrote:
Hi,
I only recently joined this group, but in answer to rob, the best oil
would be a long chain parrafin, can be purchased for vacuum pumps,
also a solid encapsulation will shift as it ages, and that would put
strain on the resistors, so they would need an initial wrap in a
silicone perhaps? definately a very compliant cover of some sort to
isolate the strain.
Mike
PS I am shortly going to set up some LTZ's for a small family of
references to age and compare. Doing the sums a difference measure
between each one and graphed will tell me which ones are the most
stable, then after a year or so splash out and get one calibrated
against a known source.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
-----Inline Attachment Follows-----
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
Op 23-8-2011 10:54, m k schreef:
Hi,
The troublesome part is the "cyclo-parraffinic" oil, that means you do have some benzene rings in there
A cyclo-alkane is definitely not a benzene ring.
Hi,
I'd go for the 70 or 90 weight Clarion oil rather than the heavy stuff. The Vitamin E is less than 1%, probably trace, the spec says it is 100% oil.
Robert G8RPI
--- On Tue, 23/8/11, m k m1k3k1@hotmail.com wrote:
From: m k m1k3k1@hotmail.com
Subject: Re: [volt-nuts] Resistance standard
To: volt-nuts@febo.com
Date: Tuesday, 23 August, 2011, 13:09
Hi,
Well I had a look at both those sites, this tells you about the oil:http://docs.clarionlubricants.com/msds_pi/C10107.pdfIt is certainly parraffinic in nature, as the high pressure hydrotreatment would get rid of any double bonds ( think ethylene etc )The vitamin e treatment may lower the conductivity a bit? but most likely not enough to be of concern.That page also leads me to think that the UK suppliers medic.15 is the same as the clarion 90. the 188 Centigrade flash point is plenty high enough for lab equipment usage. The medic.68/Clarion 350 would be quite syrupy and probably have too low a thermal conductivity as a consequence?
Date: Tue, 23 Aug 2011 12:36:38 +0100
From: robert8rpi@yahoo.co.uk
To: volt-nuts@febo.com
Subject: Re: [volt-nuts] Resistance standard
Hi,
I found a US and a UK supplier
Clarion 90 $88 5 Gal
http://www.clarionlubricants.com/do/product/FOOD_GRADE/633507009
UK
EXOL Medic 15 £96 25 litres
http://www.lubetechshop.co.uk/index.php?cPath=25_49
The US suppler has more datasheets and a selection of viscosity grades available.
Another source that I think has been mentioned before is animal / vet suppliers.
Robert G8RPI.
--- On Tue, 23/8/11, Rob Klein rob.klein@smalldesign.nl wrote:
From: Rob Klein rob.klein@smalldesign.nl
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement" volt-nuts@febo.com
Date: Tuesday, 23 August, 2011, 9:47
I have an L&N 10k oil-bath standard which is filled with something that
smells a lot like kerosene.
The stuff I am going to use is not a synthetic oil but, as I mentioned
earlier, a mineral oil. According to the manufacturer, it is made up of
"paraffinic and cyclo-paraffinic hydro-carbons"
Rob.
Op 23-8-2011 8:33, Robert Atkinson schreef:
I investigated this and both NIST (NBS) and NPL use refined mineral oil A.K.A liquid paraffin for room to medium temeperature baths. This is a food/pharmaceutical grade oil. It is a clear white oil, pretty much non-toxic and no disposal concerns. The materials in older standards will have been intened for immersion in this, not modern synthetic oils. A commercial food or confectionery supply house should be able to supply larger quantities at resonable cost.
Robert G8RPI.
--- On Mon, 22/8/11, Mitch Van Ochtenmitch@vincentelectronics.com wrote:
From: Mitch Van Ochtenmitch@vincentelectronics.com
Subject: Re: [volt-nuts] Resistance standard
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Date: Monday, 22 August, 2011, 23:50
Hi Rob,
ESI recommended "Drakeol 9 LT mineral oil" in their literature which I couldn't find in small
quantities. I investigated a synthetic oil replacement called SpectraSyn PAO and Exxon offered
to send a sample. After checking with a chemist at work I decided not to.
He said over many years of immersion the "long chain parrafin" as Mike mentioned would be the best, and
less likely to deteriorate the insulation than the synthetic replacement.
I have attached a chart he sent me for the group's observation.
Mitch
----- Original Message ----- From: "Rob Klein"rob.klein@smalldesign.nl
To: "Discussion of precise voltage measurement"volt-nuts@febo.com
Sent: Monday, August 22, 2011 8:10 AM
Subject: Re: [volt-nuts] Resistance standard
Hi Mike and Charlie,
For the oil, I have decided on the stuff that is sold locally as "sewing machine oil". This is a highly refined light mineral oil, guaranteed to be acid free.
As explained in my previous message, things haven't been progressing over the last 18 months, but I'm going to pick it up again soon, so stay tuned.
Best regards,
Rob.
Op 23-7-2011 19:14, Charles Black schreef:
Hi,
The traditional oil for standard resistors and oil baths is Mineral Oil. The cheapest source of Mineral Oil USP for small quantities is out local grocery store at about $5.50 per pint. It is a highly purified paraffin oil. If you need a large quantity then check out Exxon Marcol 72 which is available for about $12 per liter from Measurements International. I am trying to find a much better price since I could potentially use 157 liters if I am able to get a used bath that I know of.
Charlie
On 7/23/2011 3:03 AM, m k wrote:
Hi,
I only recently joined this group, but in answer to rob, the best oil would be a long chain parrafin, can be purchased for vacuum pumps, also a solid encapsulation will shift as it ages, and that would put strain on the resistors, so they would need an initial wrap in a silicone perhaps? definately a very compliant cover of some sort to isolate the strain.
Mike
PS I am shortly going to set up some LTZ's for a small family of references to age and compare. Doing the sums a difference measure between each one and graphed will tell me which ones are the most stable, then after a year or so splash out and get one calibrated against a known source.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
-----Inline Attachment Follows-----
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
--
Small Design
Zuiddijk 354
1505 HD Zaandam
The Netherlands
tel. +31 (0)75 77 11 740
fax. +31 (0)75 77 11 742
e-mail: rob.klein@smalldesign.nl
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.
On 08/23/2011 02:33 AM, Robert Atkinson wrote:
I investigated this and both NIST (NBS) and NPL use refined mineral
oil A.K.A liquid paraffin for room to medium temeperature baths.
This is a food/pharmaceutical grade oil. It is a clear white oil,
pretty much non-toxic and no disposal concerns. The materials in
older standards will have been intened for immersion in this, not
modern synthetic oils. A commercial food or confectionery supply
house should be able to supply larger quantities at resonable cost.
To echo that thought, my company makes induction heaters. For some
smaller ones we build up the resonating cap from CDE tubular
polypropylene caps soldered to bus bars. Very high current (>1000 amps)
at low RF is involved so the caps need cooling.
I asked CDE about immersing them in mineral oil and in turn cooling the
mineral oil with a radiator. They didn't recommend it. I had been
running a prototype for several months without problems so I decided to
go ahead with the technique. At the same time I set up a test.
I immersed 3 caps in the oil. Every few months I take them out and
evaluate their parameters. That experiment started 3 years ago.
Absolutely no change in any parameter or appearance. Mineral oil is
about the most benign substance one can immerse electronics in.
I should also note that the oil has not gone rancid, changed colors,
filmed over, left deposits on the bottom of the container or otherwise
misbehaved. The container is covered but not sealed.
The oil I use is USP grade intended as a livestock laxative. A gallon
costs about $9 and a 5 gallon pail about $35 from the local Farmer's Co-Op.
John
--
John DeArmond
Tellico Plains, Occupied TN
http://www.neon-john.com <-- email from here
http://www.johndearmond.com <-- Best damned Blog on the net
PGP key: wwwkeys.pgp.net: BCB68D77