QHY CFW3M-US The QHY CFW3M-US is a seven-position motorised filter wheel for 36 mm unmounted filters. A direct-drive motor takes the shortest route between positions, reducing unnecessary carousel movement.
Manufacturer model: QHY CFW3M-US · Specifications checked against manufacturer data on 2026-11-03
The QHY CFW3M-US is a seven-position motorised filter wheel for 36 mm unmounted filters. A direct-drive motor takes the shortest route between positions, reducing unnecessary carousel movement.
Filter clearance and optical spacing
The published body backfocus contribution is 17 mm, with a further 2 mm legacy adapter contribution where that adapter is required. Newer compatible direct connections can omit it. The usable filter-height limit is 5.5 mm; clearance must still be left for rotation. Weight is Approximately 700 g.
Two control arrangements
Use either the QHY camera-control connection or USB-control mode. The QHY 4-pin cable carries both power and commands. In USB mode the wheel can require 780 mA, beyond the 500 mA limit of some USB 2.0 ports; QHY documents auxiliary 12 V power through a 12 V-to-RJ11 cable for that case.
Installation and software
Do not connect USB while operating through the camera-control cable. Select the corresponding ASCOM driver and interface mode. Use plastic gaskets or the manufacturer’s filter masks to retain unmounted glass without pressing metal directly against the filter. The reset button returns the carousel to position 1.
Use the named-model manufacturer connection diagram and the backfocus reference for the selected adapter. Readout mode and output format affect frame rate, noise and full-well capacity.
Additional specifications
Body backfocus (mm)
17
Legacy adapter backfocus (mm)
2
Usable filter height limit (mm)
5.5
Control options
USB control or QHY 4-pin camera control
Camera control power
12 V carried by QHY 4-pin cable; no separate supply in this mode
USB current requirement ma
780
Auxiliary power
12 V-to-RJ11 cable can supply power in USB-control mode where USB current is insufficient
Connection restriction
Do not connect USB while using the camera-control cable
QHY CFW3M-US The QHY CFW3M-US is a seven-position motorised filter wheel for 36 mm unmounted filters. A direct-drive motor takes the shortest route between positions, reducing unnecessary carousel movement.
Manufacturer model: QHY CFW3M-US · Specifications checked against manufacturer data on 2026-11-03
