Download little cards IES + viewer (IES viewer) is very convenient.
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Allegory, the causes can be many.
Firstly, as the mOPs said , your ieski can simply be pushed into the body of luminaire models and their glow just not visible because it is blocked by geometry.
Secondly, different illumination IES files looks differently, including the shape and direction of the emission can be very different. It is everyday situation where CHD illumination directed in the opposite direction. The opposite direction of the normal / target with VRayIES.
In any case, your VRayIES, looks very strange. No target has not seen, on the container Lite, etc .. Theoretically, VRayIES-rendered faster than maksovsky Photometric Light, but the second is much more convenient. That there is only one Distribution Zone, with built-in viewer IES. So what if you're more render time not confused, it is better to use maksovskim fotometrikom. It is more technologically practical and easy to use.
Third, depending on the exposure of your 3d scenes , require different brightness (moshnost) light sources so that they became visible glow. Therefore, alternatively, try to increase the brightness of your source, two, three, ten to twenty times. While it will not be visible. If it does not, then see the first two points😉