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"8700 Sprint 3" Treadmill Display Board - New Design
The 8700 Sprint 3 will consist of a new display board mounted in the upright. It will communicate to the high power relays and KBWT motor control board located at the bottom of the treadmill via
Motor Control:
A DC motor mounted in the lower motor pan shall be controlled by an "off the shelf" motor controller manufactured by KB electronics - specifically
120VAC power shall be provided to the KB motor control board via 6VDC relay mounted to the lower motor pan. The display board shall provide 6VDC power for this coil and control the coil via signal called "BELT RELAY" which can be directed to ground in the upper display board.
Speed Sensor.
The display board shall control speed either in a closed loop or open loop mode depending on the
software installed. In the closed loop mode a GT101 speed hall effect speed sensor by Honeywell shall provide 12,800 pulses/minute at a speed of 1.0 mph. In the open loop mode the speed sensor shall act as a safety watchdog to detect runaways. In the event of the runaway, power to the motor control relay shall be removed. Speed range is 0.1 to
12.0mph. The Display board shall be responsible for provide +5VDC to this sensor as well as reading "SPEED SENSE"
Electric elevation
(2)
Elevation Grade Sense
A elevation grade pot wiper shall be used to indicate the percent elevation to the upper display board. The upper board shall provide power to drive this grade pot and shall read the analog voltage "GRADE SENSE"