Fluke 5608-12-X Secondary PRTs

The Fluke 5608 thermometer is classified as secondary standard. A secondary standard is used to transfer the ITS-90 from a standards laboratory to a customer’s laboratory.

Reference 3057043-X

Brand Fluke Calibration

*** Please Note: When ordering also specify the termination you require, ie. Fluke 5608-12-G (gold pins). X = termination ***

Specify “B" (bare wire), “D" (5-pin DIN for Tweener Thermometers), “G" (gold pins), “I" (INFO-CON for 1521 or 1522), “J" (banana plugs),
“L" (mini spade lugs), “M" (mini banana plugs), “P" (INFO-CON for 1523 or 1524), or “S" (spade lugs).
All models come without calibration unless calibration is purchased separately.

The Fluke Calibration Platinum Resistance Thermometers (PRT) models 5608 and 5609, are designed to be a secondary standard interpolating instrument converting temperature to resistance. The PRTs are used with a readout device to detect temperature changes or actual temperature.

The 5608 is also a ± 7 mK probe at the triple point of water, but its one-eighth inch (3.18 mm) diameter gets you accurate measurements from –200 °C to 500 °C with only 80mm (3.1 in) of immersion. When looking for improved response time and reduced stem effect in shallow immersion, look for small diameter probes, because the measurement error called stem effect is caused by the diameter of the stem rather than the length of the stem.

The Fluke 5608-12-X probe has an Inconel™ sheath and is made using a special manufacturing process, giving it great precision over a wide temperature range. The sensors for these probes are reference-grade platinum and feature four-wire connections with less noisy measurements than two-wire counterparts.

In order for any instrument to be used as a standard it must be calibrated. These instruments are sold uncalibrated unless calibration is requested at time of purchase. They are satisfactory as secondary standards and may be calibrated by comparison to primary standards.

FEATURES:

Secondary Reference PRT, 12 in x 1/8 in, –200 to 500 °C, lead wire (cable) 6 ft.
Calibration not included.

Fluke 5608 & 5609 Specifications

Temperature range	5608: –200 °C to 500 °C 5609: –200 °C to 670 °C.
Nominal resistance at 0.01 °C	100 Ω ± 0.5 Ω.
Temperature Coefficient	0.0039250 Ω/Ω/°C.
Accuracy [1]	See footnote.
Short-term repeatability [2]	± 0.01 °C at 0.010 °C ± 0.02 °C at max temp.
Drift [3]	± 0.01 °C at 0.010 °C ± 0.02 °C at max temp.
Hysteresis	± 0.01 °C maximum.
Sensor length	30 mm ± 5 mm (1.2 in ± 0.2 in).
Sensor location	3 mm ± 1 mm from tip (0.1 in ± 0.1 in).
Sheath material	Inconel™ 600.
Minimum insulation resistance	5608: 500 MΩ at 23 °C, 20 MΩ at 500 °C 5609: 500 MΩ at 23 °C, 10 MΩ at 670 °C.
Transition junction dimensions	71 mm x 12.5 mm (2.8 in x 0.49 in).
Minimum immersion length^[4] (<5 mK error)	5608: 80 mm (3.1 in) 5609: 100 mm (3.9 in).
Maximum immersion length	305 mm (12 in).
Response time^[5]	5608: 9 seconds typical 5609: 12 seconds typical.
Self heating (in 0 °C bath)	5608: 75 mW/°C 50 mW/°C.
Lead-wire cable type	Teflon,™ 24 AWG.
Lead-wire length	1.8 m (6 ft).
Lead-wire temperature range	-50 °C to 250 °C.
Calibration	Calibration not included; NVLAP-accredited calibration optional, lab code 200348-0. Please see calibration uncertainty table and its explanation of changeable uncertainties.
[1] “Accuracy” is a difficult term when used to describe a resistance thermometer. The simplest way to derive basic “accuracy” is to combine the probe drift specification and calibration uncertainty with readout accuracy at a given temperature. [2] Three thermal cycles from min to max temp, includes hysteresis, 99.9 % confidence. [3] After 100 hours at max temp, 99.9 % confidence. [4] Per ASTM E 644.