We had a similar enquiry to one we get quite often – a customer with a wash-down line, this time needing a slightly bigger and higher-resolution encoder than the standard size for their application. They’d looked at our HD20 but needed a larger shaft/bore option and a bit more resolution headroom.
This looks simple, but it’s worth checking the exact frame size, resolution and shaft/bore size before quoting, because the Hengstler HD20 and HD25 look almost identical from the outside but are not interchangeable – the HD25 is a larger 2.5″ frame (versus 2.0″ for the HD20) and supports a bigger bore option.
In actual application, the Hengstler HD25 is built for the same kind of harsh, corrosive wash-down environments as the HD20 – it carries an IP67 rating (NEMA 6 enclosure) and is available with anodized aluminum, stainless steel, or nickel-plated housing. It’s an optical incremental encoder with a 2.5″ flange, shaft or hollow-bore mounting (3/8″, 10mm or 12mm), resolution up to 20,000 PPR, and runs on 5-26VDC supply with a choice of Open Collector, Open Collector with Pull-Up, Push-Pull, DLD 7272 or DLD 4469 output. Operating temperature range is -40°C to +100°C. There is also a separate intrinsically safe ATEX/UL/IECEx version (the HD25 Hazardous series) for classified hazardous areas.
From our experience, before we quote this, we would normally check the exact housing material, resolution (PPR), shaft or hollow-bore size, output type, and whether the application is a classified hazardous area or not. Hope this helps.
