H Tinsley Standard Resistor Type 4405 - Information Request

[pmmunro]

Can anyone help with information on a H. Tinsley Standard Resistor Type 4405 please?

I have contacted Tinsley - now Sifam Tinsley - who replied very promptly but are not able to help as this is apparently a "very old piece of equipment" and they no longer have records.

Would anyone have a catalogue or data sheet which would have figures for the stability and tolerance of this unit please?

The resistor is rated at 0.3A and the resistance wire, probably manganin, is wound on a brass tube insulated with what looks like synthetic resin bonded paper. The resistance has been measured as within 0.1% using a 5 1/2 digit bench multimeter.

PMM

[Marconi_MPT4]

A spec for Tinsley standard resistor type 4405 from their 2000/2002 catalogue.

Rich

[Craig Sawyers]

Very old piece of equipment - like still in the Tinsley catalogue a mere 20 years ago!

Craig

[pmmunro]

Rich,

Many thanks for the information. It's just what I needed to know.

The supplementray question is; does "Grade 2" mean that Type 4405 was always specified as grade 2, or was there a better version of this type? Presumably it's Tinsley's Grade 2 as they would have specified a BS number if it was that type of grade.

Craig,

To me too it seems like a sad reflection on something that a device that was made 20 years ago, but to a standard that it could last a lifetime, should be considered too old to be worthy of consideration. Also, if the type lasted until the catalogue was digitised, why dispose of the data when it might still be of use to customers?

PMM

[Marconi_MPT4]

Originally Posted by pmmunro

Rich,The supplementary question is; does "Grade 2" mean that Type 4405 was always specified as grade 2, or was there a better version of this type?

Without the full data sheet for Type 4405, it is difficult to say if a Grade 1 version existed. All the designated Grade 1 resistor part numbers appear to begin with a 5 so would be a type 5xxx. They are also characterised as being stable to within 1 ppm over a period of ten years.

According to their notes, maximum dissipation for the resistors is 1 Watt but the highest performance will be obtained with a dissipation of 10 mW which is the ideal working condition. No harm will occur if the dissipation is increased to 1 watt but self heating will take effect after a few minutes. A grade 1 type is usually hermetically sealed in a stainless steel container which is filled with oil. Provision is made for inserting a thermometer but the resistors are intended to be used in an oil bath which is temperature controlled.

Rich

[pmmunro]

Many thanks again Rich.

PMM