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TQC Sheen Sling Psychrometer
Our TQC Sheen Sling Psychrometer accurately determines percentage relative humidity without the need to consult complex tables.
£133.00 Ex. VAT
Dispatched within 2 days
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Modal Gallery Slideshow
Our TQC Sheen Sling Psychrometer accurately determines percentage relative humidity without the need to consult complex tables.
£133.00 Ex. VAT
Dispatched within 2 days
Pay securely with
Brought to you by TQC Sheen, our paint testing specialist testing brand, we are able to offer a simple but effective Sling Psychrometer.
The Bacharach-type sling psychrometer is an affordable way to measure relative humidity levels quickly and accurately, without the need to consult complex tables. The Sling Psychrometer is designed for indicating percent relative humidity on the basis of the wet bulb-dry bulb thermometer principle.
The Sling Psychrometer is designed with portability in mind and can easily be carried and used when required. The instrument is robust and equipped with a conversion scale for calculating the percent relative humidity.
When not in use, the sling psychrometer cases telescopes into the handle for protection.
Relative humidity can be measured by an instrument called a hygrometer. The simplest hygrometer – a sling psychrometer – consists of two thermometers mounted together with a handle attached on a chain. One thermometer is ordinary, and the other has a cloth wick over its bulb and is called a wet-bulb thermometer.
When a reading is to be taken, the wick is first dipped in water and then the instrument is whirled around. During the whirling, the water evaporates from the wick, cooling the wet-bulb thermometer. Then the temperatures of both thermometers are read.
If the surrounding air is dry, more moisture evaporates from the wick, cooling the wet-bulb thermometer more so there is a greater difference between the temperatures of the two thermometers. If the surrounding air is holding as much moisture as possible – if the relative humidity is 100% – there is no difference between the two temperatures.
The tables below can be used to estimate the relative humidity of air if dry and wet bulb temperatures are known.
| Relative Humidity – RH(%) | ||||||||
|---|---|---|---|---|---|---|---|---|
| T db – T wb ( o C ) |
Dry bulb temperature – T db ( o C ) | |||||||
| 15 | 18 | 20 | 22 | 25 | 27 | 30 | 33 | |
| 1 | 90 | 91 | 91 | 92 | 92 | 92 | 93 | 93 |
| 2 | 80 | 82 | 83 | 84 | 85 | 85 | 86 | 87 |
| 3 | 71 | 73 | 75 | 76 | 77 | 78 | 79 | 80 |
| 4 | 62 | 65 | 67 | 68 | 70 | 71 | 73 | 74 |
| 5 | 53 | 57 | 59 | 61 | 64 | 65 | 67 | 69 |
| 6 | 44 | 49 | 52 | 54 | 57 | 59 | 61 | 63 |
| 7 | 36 | 42 | 45 | 47 | 51 | 53 | 55 | 58 |
| 8 | 28 | 34 | 38 | 41 | 45 | 47 | 50 | 53 |
| 9 | 21 | 27 | 31 | 34 | 39 | 41 | 45 | 48 |
| 10 | 13 | 20 | 25 | 28 | 33 | 36 | 40 | 43 |
| Relative Humidity – RH(%) | ||||||||
|---|---|---|---|---|---|---|---|---|
| T db – T wb ( o F ) |
Dry bulb temperature – T db ( o F ) | |||||||
| 60 | 64 | 68 | 72 | 76 | 80 | 84 | 88 | |
| 1 | 94 | 95 | 95 | 95 | 96 | 96 | 96 | 96 |
| 2 | 90 | 90 | 90 | 91 | 91 | 92 | 92 | 92 |
| 3 | 84 | 85 | 85 | 86 | 87 | 88 | 88 | 89 |
| 4 | 78 | 80 | 81 | 82 | 83 | 84 | 84 | 85 |
| 5 | 73 | 75 | 76 | 78 | 79 | 80 | 80 | 81 |
| 6 | 68 | 70 | 72 | 73 | 75 | 76 | 77 | 78 |
| 7 | 63 | 66 | 67 | 69 | 71 | 72 | 73 | 74 |
| 8 | 58 | 61 | 63 | 65 | 67 | 68 | 70 | 71 |
| 9 | 54 | 57 | 59 | 61 | 63 | 65 | 66 | 68 |
| 10 | 49 | 52 | 55 | 57 | 59 | 61 | 63 | 64 |
Alongside the Sling Psychrometer, we are also pleased to be able to offer other hygrometers. For instance, you may be interested in our Thermo Hygrometer, or our Digital Thermo Hygrometer. Additionally, we can also provide a Basic Inspection Kit, which is filled with a range of handy test and inspection tools and devices.
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High-quality replacement thermometer for the TQC Sheen Sling Psychrometer to ensure precise temperature readings.
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A 1-meter replacement wick for the TQC Sheen Sling Psychrometer to support accurate and efficient performance in humiidty measurements.
SKU: TM0081
Applications: Corrosion Testing, Temperature and Climatic Testing
Materials: Aluminum, Metal, Paints and Coatings , Plastics and Polymer, Steel
Calibration Available
Declaration of Conformity
A sling psychrometer is a manual, mechanical instrument for measuring relative humidity using the wet bulb-dry bulb thermometer principle – two matched thermometers, one with a wetted wick around the bulb, are swung through the air on a handle. Evaporation cools the wet bulb; the temperature difference between wet and dry readings gives ambient relative humidity. The TQC Sheen Sling Psychrometer (TM0081) is a Bacharach-type design with an affordable price point and no batteries or electronics – just two calibrated thermometers, a wick, a water reservoir and a swinging handle.
Before applying a protective coating, surface temperature must remain above the dew point of the surrounding air – otherwise condensation forms on the substrate and disrupts coating adhesion, cure and long-term performance. Measuring relative humidity is the first step in calculating dew point. Coating inspectors, applicators and QC teams use a sling psychrometer as a low-tech, battery-free way to spot-check ambient RH at the point of coating – often paired with the TQC Sheen Dew Point Calculator to convert wet/dry bulb readings directly to dew point and RH without lookup tables.
The TQC Sheen Sling Psychrometer measures relative humidity from 10% to 100%. The thin bulb design gives fast thermal response – typical stabilization time on the wet bulb is under a minute of consistent slinging. The built-in water reservoir holds enough water for several hours of testing without refilling – practical for field inspection days where continuous access to distilled water is limited. The instrument is compact and portable and can easily be carried between inspection points in a shipyard, site or lab.
Yes – the wick is a consumable and should be replaced when it becomes dirty, stained or damaged. A dirty wick affects the wet bulb reading and skews RH results. TQC Sheen Spare Wick is available as a 1-metre replacement roll – cut a fresh section as needed and slide it over the wet bulb thermometer. Typical replacement frequency is annual for regular users or immediately if the wick shows staining or damage. Store the psychrometer with the reservoir empty when not in daily use to prevent stagnation.
The Sling Psychrometer pairs directly with the TQC Sheen Dew Point Calculator for instant dew point and RH readings without lookup tables. For digital, electronic readings the TQC Sheen Hair Hygrometer and Digital Thermo Hygrometer are companion instruments. For advanced continuous dew point recording on-site, the TQC DewCheck 4 Series 2 dewpoint meter provides real-time data logging across all the climate parameters needed to treat surfaces effectively. For surface temperature verification alongside ambient RH, add the TQC Sheen Magnetic Thermometer (TM0015).
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