PHzMonitor Model 9 - Frequency Measurement
From GridTrak
Contents |
Sensor Frequency Measurement and Transmission Modes
Single or Dual Channel
The sensor uses two OpAmp channels and micro controller inputs triggered at +2.5Vdc. The channels are complimentary half waves from each side of the rectifier.
- Measure Every Cycle @ 2.5V (single channel mode)
In 2.5V mode, a single channel's frequency is measured, triggered at +2.5Vdc on the half wave.
- Measure Every Cycle @ 0 V (dual channel mode)
In 0V, Zero Crossing Mode, the time between +2.5Vdc on channel 1 to -2.5Vdc on channel 2 is measured and zero crossing is calculated as the mid point. The time between zero cross points is used to calculate the frequency.
Maintain a data set of the last n samples (n <= 600)
- Calculate the average of the data set
- Averaging Method 0 (default) = Average = Sum(samples)/Count(samples)
- Averaging Method 1 = For each sample: Average = (Sample[n] + Average / 2)
Transmit a packet ID and the following data depending on configuration modes
Normal Mode (default)
- Transmit the Last Sample (RAW frequency 1 or 2 above), the Average (5a or 5b above) of the data set, and the Delta Z(3 above)
Step Modes
- Same dataset as normal mode, but transmit After each count of cycles has completed
- Mode 1 = Transmit Last Sample(RAW frequency 1 or 2 above), Average (5a or 5b above) of data set, and Delta Z (3 above)
- Mode 2 = Transmit Last Sample(RAW frequency 1 or 2 above), Mean of data set, and Delta Z (3 above)
- Mode 3 = Transmit and Average (5a or 5b above), Mean of data set, and Delta Z (3 above)
