A treater's zero speed range is very useful if you are running material at a low line speed and don't want to treat it. However, if you are trying to treat at low line speeds, you need to be sure the zero speed range is not set too high.
The Series 2000 power supply has an internal zero speed interlock. This interlock will not allow the power supply to start until a preset speed is achieved. In other words, the unit will not treat any material that is running under the preset speed whether the line has just begun running or has been running previously and has just decreased below the preset speed.
Generally the line speed is factory calibrated to 30 feet per minute. Depending on the line operational requirements, this may require field adjustment. This adjustment is a very simple procedure, only requiring the adjustment of a single potentiometer at your lowest line speed.
The speed circuit on the LM4027 control board (pictured) signal comes from the sensor mounted in the station. This sensor develops a pulse rate from either a 60 tooth gear, an encoder (proportional speed) or from the bolt heads on a wheel (zero speed) attached to the ground roll. The speed range for the interlock can be adjusted using the potentiometer, R91 - ZERO SPEED, on the control board (Detail "A"). Turning the potentiometer clockwise will increase the zero speed set point, and conversely, turning the potentiometer counter clockwise will decrease the zero speed set point.
After making any adjustments to the zero speed set point, ensure that the power supply deenergizes when the line speed falls below the desired speed or when the ground roll stops.