SMT8_4 TECHNICAL MANUAL

Perfect Power Online Manuals.

 

Support for your SMT8 V4 Unit.

FREQUENCY MODIFICATION

The SMT8_4 has a separate FREQUENCY/PWM modification channel for the purpose of tuning a digital signal. These signals are used in airflow meters and solenoid drives. The SMT8_4 can tune the ON and OFF periods of the signal simultaneously in the frequency mode, or just the ON period length in the PWM mode

SMT8V4 Piggy-Back Unit - F6 - Frequency/PWM Map

 

ASSOCIATED PINS

 

FREQUENCY INPUT Pin 2 of 12 FREQ (IN)
FREQUENCY OUTPUT Pin 2 of 10 FREQ (OUT)

 

SMT8V4 Piggy-Back Unit - PWM/Frequency Wiring

PWM/FREQUENCY WIRING

 

For hall or optical sensor a pull-up is required. See diagram below.

 

SMT8V4 Piggy-Back Unit - Hall/Optical Sensor Wiring

 

COMPLETE CALCULATION

 

FREQ (Output) =
 

FREQIN
+-Freq AMP
+-Freq ENGT
+-Freq AIRT


The output is limited to the High/Low Frequency parameter. Entry is in PERCENT. The PWM modification is calculated the same way as for the Frequency modification, but the limit parameters do NOT apply.