|
All trim adjustment potentiometers on the control logic printed circuit board assembly are preset at the factory. Some trim potentiometers and switches have been made available for adjustment by the customer. All adjustable devices are explained below, including those which have been factory sealed. Adjustable components are located as shown here.
CAUTION: The potentiometers which have been sealed must not be readjusted since readjustment may cause damage to the motor and/or drive.
| R9 | -6V Reference | This pot adjusts the reference level for the DC bus over and under voltage fault trip logic circuits. CAUTION: This pot is factory sealed. Do not attempt to readjust this pot. |
| R18 | Current Trip | This pot controls the maximum motor current trip level and is normally factory set at 150% of rated drive current. CAUTION: This pot is factory sealed. Do not attempt to readjust this pot. |
| R19 | Acceleration (Current) Limit | This pot is normally set fully clockwise at the factory. To achieve a minimum acceleration time and prevent nuisance tripping with large inertial loads, the potentiometer may be adjusted slowly counterclockwise until tripping under acceleration ceases. If the potentiometer is set too far counterclockwise, the motor may not accelerate up to full (set) speed. |
| R28 | Minimum Frequency Adjust | If a minimum frequency (speed) other than zero is desired, adjust the main speed control (pot) to zero speed and rotate R28 clockwise until the desired minimum frequency (speed) is achieved. NOTE: Not effective when Digital thumbwheel input option or BCD interface is installed. |
| R29 | Maximum Frequency Adjust | The low range maximum frequency is factory set at 60 Hz unless otherwise specified. The frequency is then field adjustable between 50 and 90 Hz. NOTE: Frequency adjustment on high range units is 90 to 200 Hz. High range units are factory set per customer order by adding a 1.13K type RN60D resistor in location R36A on the logic assembly board. |
| R62 | Deceleration (Current) Limit | This pot is normally set fully clockwise at the factory. To achieve minimum deceleration time and minimize nuisance trippping with large inertia loads, the potentiometer may be adjusted slowly counterclockwise until the tripping under deceleration ceases. If the potentiometer is set too far counterclockwise, the motor may remain at some preset speed and not decelerate to minimum speed. |
S1 |
DC Boost | Switch S1 is a 16 position hexadecimal switch which sets the motor starting or breakaway torque. When S1 is in position 15, the motor has maximum starting torque; when S1 is in position 0, the motor has minimum starting torque. |
| S2 | Acceleration | When S2 is in position 15, the motor will accelerate most rapidly to preset speed; when S2 is in position 0, the motor will accelerate most slowly to preset speed. |
| S3 | Deceleration | When S3 is in position 15, the motor will decelerate most rapidly to preset speed; when S3 is in position 0, the motor will decelerate most slowly to preset speed. The drive is designed to prevent nuisance tripping on deceleration with high inertial motor loads. If the motor decelerates more slowly than desired atan optimum maximum deceleration rate with high inertial loads, it is recommended that dynamic braking be employed. |
| S4 & S5 | Volts Per Hertz | The Volts/Hz level is setable by means & of switches S4 and S5. Switch S4 sets the normal Volts/S5, Hz level and switch S5 sets the low frequency Volts/Hz level. NOTE: If occasional tripping occurs with low efficiency motors, set Volts/Hz one to two values lower. |
**click above table for larger image (156Kb.jpg)