Marble Automation developed the MS 921B
propeller revolution counter to count the number
of revolutions of a propeller or other rotating
parts. The LED display clearly shows the number
of revolutions per minute. The LEDs also show
the direction of revolution of the propeller.
The MS 921B can be applied in a wide range of
situations. The rpm of a winch, (dredging) pump
or bowthruster can all be measured.

Advantages

• Clear and reliable 4 digit display of the number of revolutions per minute
• Indication of direction of revolution of the propeller
• Relay output that switches automatically after a pre-determined number of revolutions per minute
• Compact shape
• Easy installation and configuration

Features

• Dimensions: 96x72x75 (WxHxD)
• Cut out: 92x68 (WxH)
• Power supply: 24VDC
• Output: 1 relay
• Input: 2 proximity switches
• RS485 modbus interface
• Sensors exluded