©Isothermal Technology
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914 millisKanner manual Iss. 1.00
thermometer in the furnace. Whilst the milliK is designed to reject common-mode
DC and AC signals (at both 50 and 60Hz), it is good practice to minimise them. It
is common practice to use a metal equalising block in a furnace when performing
comparison calibrations. This should be connected to the safety earth of the
electrical supply (most furnaces designed for temperature metrology applications
are fitted with a device to ‘earth’ the equalising block). Do not ‘earth’ the
equalising block to the screen/measurement ground terminals on the front panel
of your millisKanner or milliK as this is not connected to the safety earth of the
electrical supply.
Provide a ‘clean’ electrical environment in your temperature laboratory. It may be
useful to filter your electrical supply into the laboratory especially if other heavy
electrical machinery is being used nearby on the same supply (the milliK has very
good immunity to electrical noise conducted along the electrical supply, but other
equipment in your laboratory may be more sensitive). It is worth avoiding the use
of sources of electrical signals or noise in your laboratory. Examples include
furnaces with triac controls (especially those that ‘chop’ the electrical supply part
way through a cycle – better controllers switch only at the zero-crossing point to
‘chop’ only whole cycles), mobile phones (the millisKanner and milliK are not
significantly affected by mobile phones, but other equipment may be more
sensitive).