Overview
The DBK7 can be used for diverse frequency-monitoring applications. Typical uses include measuring the
flow of liquids with a flowmeter and measuring rotation (rpm) with a shaft encoder. The monitored
process must generate a series of electrical pulses whose frequency is related to the desired variable.
Features of the DBK7 include:
• Inputs can be analog (high or low level) or digital.
• Each channel has a programmable frequency range.
• Noise effects can be minimized by debounce, attenuation, and low-pass filtering.
• Up to 64 DBK7s can be used with a single LogBook or Daq device for a maximum of 256 channels.
The card’s basic function can be realized from the following block diagram. Each channel:
• Conditions an input signal
• Selects the signal’s rising or falling edge
• Debounces the edge
• Measures the signal’s frequency.
The D/A converter outputs a voltage from -5 V to +5 V to correspond with the selected frequency range.
The LogBook directs the card’s D/A converter to convert the data from the proper input channel.
Hardware Setup
CAUTION
DBK7 must be configured before connecting the card to inputs and outputs.
Failure to do so could result in card damage.
Hardware-related steps for setting up DBK7 include:
• Configuring the DBK7 onboard jumpers and switches for the application
(see previous CAUTION).
• Configuring the Daq device (see page 8)
• Connecting the input cables to sensors and the output cable to a Daq device or LogBook.
DBK7, pg. 2 879895 DBK Option Cards and Modules