DFE WebHandler 3 Instruction Manual page 23

Figure 18 - DC TACHOMETER CARD SWITCH SETTINGS AND ADJUSTMENTS
1. Initial Switch Settings
WARNING! To prevent possible damage to the circuit card, set the SW702 and SW703 switches as shown BEFORE
installing the card and BEFORE running the machine!
2. Run the machine at the maximum expected operating speed. Measure the line tachometer voltage and
note its polarity. This is called the
maximum speed. In this case the
3. Set the SW701 switches to accommodate the tach polarity measured at TB102 terminals 3 and 1. Use the
following charts to set the switches based on which terminal is positive polarity.
TB102 terminals
Ltach ----- if pos 1 is +
4. Set SW702 to accommodate the voltage measured in step 3 above using the chart below. If the machine
was run at half speed, multiply the voltages by 2 and use those values for the following switch-setting
chart.
VOLTS DC
3 - 4
4 - 16
16 - 64
64 - 250
5. Set the span pot. Run the machine at maximum speed. Measure the
LTACH
points TP701 (+) and TP703. Adjust the
INITIAL SW702 and SW703 SWITCH SETTINGS
1 - Open
2 - Open
3 - Open
4 - Closed
voltage. (NOTE: If desired, run the machine at 50% of
LTACH
output voltage will be set at 5.0 volts instead of 10 volts (50%).
LTACH
SW701 SWITCHES
1
NA
if pos 3 is + NA
SW702 SWITCH SETTINGS
1
Closed
Open
Open
Open
LTACH
17
(NA = Not Applicable)
2 3
NA Open
NA Closed
2 3
Open Open
Closed Open
Open Closed
Open Open
Span pot. (RT701) for 10.0 volts.
4
Closed
Open
4
Open
Open
Open
Closed
output voltage at test
LTACH