Sensing Devices is one of very few companies in the UK with the technical skills and experience to manufacture precision SPRTs that are highly stable with minimal drift.
We assemble a range of SPRTs for use in primary/secondary or industrial semi-standard applications. This includes Model S and Model Q Precision Platinum Resistance Thermometers that are generally used in laboratory environments. We also manufacture Industrial (Working) Standard Thermometers that are suitable for everyday use in on-site calibration work.
The elements in SPRTs are made from reference-grade wound platinum wire connected by platinum lead wires. Based on the temperature range, sheaths can be manufactured for a range of materials including quartz and Inconel.
Our turnkey design, manufacturing and calibration services, guarantee the reliability and accuracy of the finished SPRT.
Model S SPRTs have stainless steel sheaths and are specially designed for temperature measurement in laboratory or industrial applications and for general purpose calibrations of resistance thermometers, thermocouples or thermistor probes, in the range -100° to +450°C.
Our highly experienced technicians can advise you on the best approaches for the most demanding of applications.
SPRT is a simplex PT100 sensing element (100Ω at 0°C) housed in a metal probe.
| MODEL | S385, S390, S391 |
| TEMPERATURE CHARACTERISTICS (W VALUE) | 1,3850, 1,3900, 1,3916 |
| OPERATING TEMPERATURE | -100 to +450 deg C |
| ELEMENT | 100 +/- 0,05 ohms |
| INTERNAL LEADS | Four - wire platinum |
| EXTERNAL LEADS | 4-leads of silver plated copper wire, 19/0,15mm, PTFE insulated and with outer screen with PTFE cover, fitted with 4 spade connectors and spade connected to screen. |
| PERFORMANCE GUARANTEE | Each thermometer is supplied with a certificate giving resistance values at 0 deg C and 100 deg C obtained by comparison calibration against UKAS certified standards. |
| REPRODUCIBILITY | +/- 0,02 deg C or +/- 0.008 ohms |
| MEASURING CURRENT | 1 milliampere is recommended |
| IMMERSION DEPTH | 200 mm is recommended minimum |
| IMMERSION EFFECT | Approximately +/- 0.005 deg C when changing from 100 to 250mm immersion |
| HANDLE TEMPERATURE | 85 deg C maximum. Do not immerse beyond the sheath marking when using at 400deg C or more. |
| MATERIAL | 316 stainless steel sheath, with a Nylotron handle Sheath dia; 6,35 x 450mm handle; 115 x 25mm (nominal) |
SPRT is a simplex PT100 sensing element (100Ω at 0°C) housed in a metal probe.
| TEMPERATURE CHARACTERISTICS (W VALUE) | 1,3925 minimum |
| OPERATING TEMPERATURE | -100 to +650 deg C |
| ELEMENT | 50mm long unconstrained coil , resistance at 0deg C 25.5 ohms nominal |
| INTERNAL LEADS | Four - wire platinum |
| EXTERNAL LEADS | 4-leads of silver plated copper wire, 19/0,15mm, PTFE insulated and with outer4-leads of silver plated copper wire, 19/0,15mm, PTFE insulated and with outerscreen with PTFE cover, fitted with 4 spade connectors and spade connected toscreen . |
| PERFORMANCE GUARANTEE | Each thermometer is supplied with a certificate giving resistance values at 0 deg CEach thermometer is supplied with a certificate giving resistance values at 0 deg C and 100 deg C obtained by comparison calibration against UKAS certifiedstandards. |
| REPRODUCIBILITY | +/- 0.01 deg C (0.001 ohms) |
| MEASURING CURRENT | 1 milliampere is recommended |
| IMMERSION DEPTH | 200 mm is recommended minimum |
| IMMERSION EFFECT | Approximately +/- 0.001 deg C when changing from 100 to 250mm immersion |
| HANDLE TEMPERATURE | 85 deg C maximum. Do not immerse beyond the sheath marking when using at85 deg C maximum. Do not immerse beyond the sheath marking when using at 400 deg C or more. |
| MATERIAL | Fused quartz sheath Stainless steel fittings handle; 115 x 25mm (nominal)Nylotron |
SDL offers two platinum resistance thermometers for use as working standards. These units are suitable for everyday use in on-site calibration work.
| Model | Temperature range | Stability over range |
| SV1915 | 50/+250ºC | ±25mK |
| SV1929 | -70/450ºC | ±35mK |
