OM Manual

WT1-UWL

CCT (K)	(5700K Cool White) (3000K Warm White)
CRI (Colour Rendering Index)	85
White Lumens	(900lm Cool) (750lm Warm)
White Wattage	6W
Static Colour	Red 400lm Green 550lm Blue 350lm
RGB Wattage	9W-3W per colour
RGB Lumens	Green 172lm Red 137lm Blue 162 Total 471lm
RGBW Lumens	Green 172lm Red 137lm Blue 162 Total 471lm White 200lm
Driver Requirements	350mA Constant current MAX
Light Emitting area	45mm Diameter
Lens Type	Flat, defused
Driver Control White & RGB	PWM
Face 316 stainless	85mm
Body 316 stainless	65mm
Fixing 2” Pipe	PN9 wall 2.5 I/D53mm
White Cable	2 cores, 0.5mm2 wire size, 16/0.2mm (Blue Cathode) (Brown Anode) 6mm
RGB cable	6-core 7-2-6a PVC insulation 6mm
RGBW cable	8-core 7-2-6a PVC insulation 6mm

WT1.5-UWL

CCT (K)	(5700K Cool White) (3000K Warm White)
CRI (Colour Rendering Index)	85
White Lumens	(900lm Cool) (750lm Warm)
White Wattage	6W
Static Colour	Red 400lm Green 550lm Blue 350lm
RGB Wattage	9W-3W per colour
RGB Lumens	Green 172lm Red 137lm Blue 162 Total 471lm
RGBW Lumens	Green 172lm Red 137lm Blue 162 Total 471lm White 200lm
Driver Requirements	350mA Constant current MAX
Light Emitting area	45mm Diameter
Lens Type	Flat, defused
Driver Control White & RGB	PWM
Face 316 stainless	85mm
Body 316 stainless	65mm
Fixing 2” Pipe	PN9 wall 2.5 I/D53mm
White Cable	2 cores, 0.5mm2 wire size, 16/0.2mm (Blue Cathode) (Brown Anode) 6mm
RGB cable	6-core 7-2-6a PVC insulation 6mm
RGBW cable	8-core 7-2-6a PVC insulation 6mm

WT1.5-UWL

CCT (K)	(5700K Cool White) (3000K Warm White)
CRI (Colour Rendering Index)	85
White Lumens	(900lm Cool) (750lm Warm)
White Wattage	6W
Static Colour	Red 400lm Green 550lm Blue 350lm
RGB Wattage	9W-3W per colour
RGB Lumens	Green 172lm Red 137lm Blue 162 Total 471lm
RGBW Lumens	Green 172lm Red 137lm Blue 162 Total 471lm White 200lm
Driver Requirements	350mA Constant current MAX
Light Emitting area	45mm Diameter
Lens Type	Flat, defused
Driver Control White & RGB	PWM
Face 316 stainless	85mm
Body 316 stainless	65mm
Fixing 2” Pipe	PN9 wall 2.5 I/D53mm
White Cable	2 cores, 0.5mm2 wire size, 16/0.2mm (Blue Cathode) (Brown Anode) 6mm
RGB cable	6-core 7-2-6a PVC insulation 6mm
RGBW cable	8-core 7-2-6a PVC insulation 6mm

WT2-UWL

CCT (K)	(5700K Cool White) (3000K Warm White)
CRI (Colour Rendering Index)	85
White Lumens	(900lm Cool) (750lm Warm)
White Wattage	6W
Static Colour	Red 400lm Green 550lm Blue 350lm
RGB Wattage	9W-3W per colour
RGB Lumens	Green 172lm Red 137lm Blue 162 Total 471lm
RGBW Lumens	Green 172lm Red 137lm Blue 162 Total 471lm White 200lm
Driver Requirements	350mA Constant current MAX
Light Emitting area	45mm Diameter
Lens Type	Flat, defused
Driver Control White & RGB	PWM
Face 316 stainless	100mm Concrete 85m Liner
Body 316 stainless	65mm
Fixing 2” Pipe	1.5 BSP Thread (inlet)
White Cable	2 cores, 0.5mm2 wire size, 16/0.2mm (Blue Cathode) (Brown Anode) 6mm
RGB cable	4-core 7-2-6a PVC insulation 6mm
RGBW cable	5-core 7-2-6a PVC insulation 6mm

WT3-UWL

CCT (K)	(5700K Cool White) (3000K Warm White)
CRI (Colour Rendering Index)	85
White Lumens	300lm (Cool) (250lm Warm)
White Wattage	2W
Static Colour	Red 150lm Green 175lm Blue 185lm
RGB Wattage	9W-3W per colour
RGB Lumens	Green 72lm Red 37lm Blue 62 Total 471lm
Light Emitting area	28mm Diameter
Lens Type	Flat, defused
Driver Control White & RGB	PWM
Face 316 stainless	55mm Concrete 85m Liner
Body 316 stainless	65mm
Fixing 2” Pipe	PN12 wall 2.2 I/D37mm
White Cable	2 cores, 0.5mm2 wire size, 16/0.2mm (Blue Cathode) (Brown Anode) 6mm
RGB cable	4-core 7-2-6a PVC insulation 6mm

WT4-UWL

CCT (K)	(5700K Cool White) (3000K Warm White)
CRI (Colour Rendering Index)	85
White Lumens	(2500lm Cool) (2000lm Warm)
White Wattage	10W
Static Colour	Red 400lm Green 550lm Blue 350lm
RGB Wattage	9W-3W per colour
RGB Lumens	Green 172lm Red 137lm Blue 162 Total 471lm
RGBW Lumens	Green 172lm Red 137lm Blue 162 Total 471lm White 200lm
Light Emitting area	70mm Diameter
Lens Type	Flat, defused
Driver Control White & RGB	PWM
Face 316 stainless	130mm
Body 316 stainless	65mm
Fixing 2” Pipe	WT Niche
White Cable	2 cores, 0.5mm2 wire size, 16/0.2mm (Blue Cathode) (Brown Anode) 6mm
RGB cable	4-core 7-2-6a PVC insulation 6mm
RGBW cable	5-core 7-2-6a PVC insulation 6mm

WT5-UWL

CCT (K)	(5700K Cool White) (3000K Warm White)
CRI (Colour Rendering Index)	85
White Lumens	(1200lm Cool) (1000lm Warm)
White Wattage	6W
Static Colour	Red 400lm Green 550lm Blue 350lm
RGB Wattage	9W-3W per colour
RGB Lumens	Green 172lm Red 137lm Blue 162 Total 471lm
RGBW Lumens	Green 172lm Red 137lm Blue 162 Total 471lm White 200lm
Light Emitting area	70mm Diameter
Lens Type	Fresnel Lens
Driver Control White & RGB	PWM
Face 316 stainless	150mm
Body 316 stainless	65mm
Fixing 2” Pipe	1.5 BSP Thread
White Cable	2 cores, 0.5mm2 wire size, 16/0.2mm (Blue Cathode) (Brown Anode) 6mm
RGB cable	4-core 7-2-6a PVC insulation 6mm
RGBW cable	5-core 7-2-6a PVC insulation 6mm

1 Introduction

This test work aimed to look at one aspect of the material changes for the lighting product, investigating the integrity of the newly introduced polymer seal material at the base of the screw thread in contact with the plastic face plate. The work aimed to look for signs of seal chemical compatibility issues with chemically shock treated model pool water to reduce the chance of future field failures. It is, however, not a comprehensive range of tests of all material combinations and corrosion issues, all possible rogue pool conditions or issues with assembly or maintenance during reassembly after replacement of the LED internal light sub- module.

The test plan was to analyse the internal seal to give a baseline for the materials prior to chemical exposure testing that will be used for comparison to determine if there had been any chemical or physical change to the material. Shore hardness measurements were used to look for hardening and embrittlement physical symptoms. FTIR was used to look for changes to the surface organic chemistry of the polymers and SEM/EDX looked for signs of physical attack like cracking and crazing that might compromise the water seal for example.

2 Sample Preparation/Method Details

The Inner O-ring Seal from the LED light fitting was removed and cut in half with one half being exposed for 48 hours to the pool shock treatment and the other half being retained for comparison. See Figure 1 and Figure 2 for photographs of the seal before and after exposure.

A worst-case pool shock treatment was prepared containing approximately 30 ppm free chlorine (a normal shock treatment would be around 10 ppm) and approximately 40 ppm cyanuric acid. This was then pH adjusted to pH 7.2 using dilute hydrochloric acid.

It is important to distinguish between free chlorine and chloride as they are not the same. Chlorides form when ionic salts containing chloride ions (such as NaCl) dissociate in water. In the case of sodium chloride (NaCl) this leads to sodium ions and chloride ions surrounded by water molecules. This type of chemistry is typical in sea water.

In pool water, free chlorine is used at low levels in order to sanitise the pools and the chemistry is quite different to chloride chemistry. When a hypochlorite (such as calcium hypochlorite) is added to water it forms hypochlorous acid and a hydroxide ion, in this case calcium hydroxide.

Ca(OCl)2 + H2O  2 HOCl + 2 Ca(OH)2

One half of the O-ring seal was placed in a clean 100 mL beaker and covered in the accelerated pool shock treatment for 48 hours. The seal was then re-analysed after this treatment looking for any signs of physical or chemical degradation.

A Jasco FTIR-4100 with ATR accessory was used to obtain FTIR spectra for each of the samples.

Shore Hardness was measured on a Shore A Durometer, Model: TI-AC.

For SEM/EDX analysis samples were cut from the O-ring and seals and imaged under the optical microscope before being mounted onto SEM stubs and gold coated.

The use of gold as a coating creates a gold (Au) peak or peaks on the EDX spectra. This gold is part of the sample preparation and not part of the sample; therefore, this should be taken into account when interpreting the EDX data.

The optical microscopy was performed on a Leica MZ12 binocular microscope. The SEM and EDX analysis were performed on a Philips XL30 tungsten tip electron microscope with secondary electron and backscatter electron imaging detectors (SEM2). The beam energy used was 20keV which was high enough to include the majority of the elements in the periodic table, and low enough to minimise the electron probe sample volume. The EDX was performed on an EDAX UTW detector system.

The Optical Microscopy, SEM with EDX analysis were performed on the 25th February 2022.

The FTIR analysis and shore hardness measurements were performed on the 22nd and 25th February 2022.

The results relate to the sample as received and after suitable sample preparation for the technique used.

3 Results and Discussion

3.1 Shore A Hardness Results

Due to its size and shape the inner O-ring seal from the LED pool light was not ideal for taking Shore Hardness measurements, this led to slightly more variation in the results than would be typically seen.

Table 1 shows the results obtained for shore hardness for the inner O-ring seal both before and after exposure to the accelerated pool shock treatment.

While the values obtained varied slightly, it can be seen that there is no difference in the average hardness of the O-ring seal before and after exposure to the pool shock treatment.

Visual inspection of the O-ring seal did not show any change to its physical properties such as its elasticity or colour.

3.2 FTIR Results

Scans of the sample were taken prior to its exposure to the accelerated pool shock treatment on a Jasco FTIR-4100 using an ATR accessory.

In general, black samples lead to poor quality spectra since they absorb infrared light over a large range of frequencies. To try and offset this, a Germanium ATR crystal was used instead of the normal diamond ATR crystal. Using various settings spectra were obtained for the sample but the overall quality of the spectra was not as high as would normally be expected.

Figure 3 and Figure 4 show the FTIR spectra for the O-ring seal before and after exposure. There does not appear to be any significant differences between the FTIR spectra obtained for the O-ring seal before or after exposure to the pool treatment.

Figure 5 shows the library search obtained for the O-ring seal: This indicates that the seal is possibly an acrylonitrile / butadiene co-polymer with around a 67% match. It should be noted that the library is not a comprehensive list of all material types and manufacturer’s commercial products, so should only be treated as an indicative.

3.3 SEM/EDX Analysis

Optical microscopy, SEM and EDX analysis were used to look for any differences between the before and after exposure O-ring samples. More emphasis was placed on examining the surfaces of the components as this is where any damage would be more apparent. The bulk material of the O-ring was also examined by taking selected cross-sections of the O-ring.

The components looked near-identical using the optical microscope in Figure 6 to Figure 9, so the samples were prepared for SEM/EDX analysis, looking at both the surfaces and the cross-sections of the O-ring.

Both secondary electron imaging and backscatter imaging techniques were used to look at the surfaces of the components. Backscatter gives information on elemental composition based on contrast, i.e. the brighter the contrast, the heavier the element. Secondary electron imaging provides more topographical detail of the surfaces examined.

The O-ring had a slightly textured surface i.e. moulding striations are visible, and brighter contrasting filler particles can be observed in the Backscatter images.

Comparing both low and high magnification images for the O-ring before and after exposure (Figure 10 and 11 compared with Figure 16 and 17), a slight difference in the surface of the O-ring after exposure was observed. Small holes were observed on the surface after exposure suggesting that the shock treatment may have removed some of the filler particles from the matrix. Removal of filler particles could potentially result in leaks over the lifetime of the seal. However, no cracking/crazing or swelling of the surface was observed. EDX analysis in Figure 15 and Figure 21 showed the elemental composition of the external surfaces of the O-rings before and after exposure were near-identical.

The EDX spectra show that the O-rings contain carbon, nitrogen, oxygen, sodium sulphur, calcium and zinc. This is in keeping with the FTIR findings as carbon, nitrogen and oxygen are consistent with acrylonitrile/butadiene. The calcium and sodium are likely to have originated from the filler materials and the zinc and sulphur are possible cross linking/curing agents used in the material.

The bulk analysis was conducted on a freshly cut section of the material.

The bulk of the O-ring was examined to look for differences in elemental composition and filler material distribution after exposure to the pool shock treatment. No differences were found meaning that the shock treatment did not affect the bulk of the material which is logical since no effects of the shock treatment were observed in the surface analysis.

Small holes were observed on the cross-sections of the O-ring both before and after exposure. The holes on the cross sections are from removal of filler particles but this occurred as a consequence of sample preparation and should be ignored in this instance. When the sample was cut, the blade dislodged these filler particles.

4 Conclusions

FTIR and EDX analysis suggested that the accelerated pool shock treatment does not appear to have had any adverse effect on the chemical composition or structure of the O-ring, however, SEM analysis of the surface of the O-ring suggested that the pool shock treatment may have caused loss/dissolution of filler particles which could potentially result in leak paths being created.

Primary Author: Matthew Edwards & Dr Kim Nickson Function: Analytical Chemist & Senior Chemist / Lab Manager Signature: (hard copy only)________________

End of Report