Measurement Computing DBK Part 2 - Manual (Page 218)

pg. 12, DBK202, DBK203, and DBK204 Series 938994 DBK Option Cards and Modules
Adding Resistor/Capacitor Filter Networks
WARNING
Disconnect the DBK202, DBK203, DBK203A, DBK204, or DBK204c from power and
from signal sources prior to installing capacitors or resistors.
CAUTION
Ensure wire strands do not short power supply connections (+15 V, -15 V, +5 V, etc.) to
any terminal potential. Failure to do so could result in damage to DaqBook/2000 Series
devices, DaqBoard/2000 Series boards, or DaqBoard/2000c Series boards.
Do not exceed maximum allowable inputs (as listed in product specifications). There
should never be more than 30 V with reference to analog ground (AGND) or earth
ground.
Do not operate DBK202 on an exposed metal surface.
You must provide strain-relief (lead slack) to all leads leaving DBK202, /203, /203A,
/204, or /204c. Use tie-wraps [not included] to secure strain-relief.
Always connect the CHASSIS terminal to earth ground. This will maximize static
protection.
You can install customized RC filter networks to improve the signal-to noise ratio when an unacceptable
level of noise exists. DBK202, /203, /203A, /204, and /204c include sockets for installing RC filter
networks directly on the board.
The following table contains values that are typical for RC filter network components.
Typical One-Pole Low Pass Filter Values
for DBK202, DBK203, DBK203A, DBK204, and DBK204c
R C f f
Ohms µF Hertz (-3dB) kHz (-3dB)
510 1 312 0.31
510 0.47 664 0.66
510 0.22 1419 1.42
510 0.1 3122 3.12
510 0.047 6643 6.64
510 0.022 14192 14.19
510 0.01 31223 31.22
510 0.0047 66431 66.43
470 0.0033 102666 102.67