Rockford Systems, LLC
Call: 1-800-922-7533
16
SECTION 4—TROUBLESHOOTING
Adjustable Stroke Detect-A-Finger
®
Drop-Probe Device
SYMPTOM 1
After turning on the air supply (but not the electrical power), the sensing probe travels to bottom of stroke.
SOLUTION
Verify all electrical power to the machine is turned off and verify this by using an electrical volt meter. Verify the air supply to the machine
is turned on.
Make sure the right-hand side of the mini air filter-regulator assembly (feeding the drop-probe assembly) is adjusted down to 0 PSI and
the left-hand side is set to around 15 PSI. (Turn adjustment knob counterclockwise to decrease air pressure and clockwise to increase
air pressure.) Verify the air tubes are going to the proper locations on the air cylinder in the drop-probe assembly. Depress the tubing
release ring of the bottom 90º air-tube fitting on the air cylinder and remove the air tube. Depress the tubing release ring of the top 90º
air-tube fitting on the air valve and remove the air tube. Install the tube that is blowing air to the bottom 90º air-tube fitting on the air
cylinder. Install the remaining air tube to the top 90º air-tube fitting on the air valve.
SYMPTOM 2
After turning on electrical power (without actuating the foot switch), the sensing probe travels to bottom of stroke.
SOLUTION
Verify SYMPTOM 1 is not the cause of the problem before proceeding.
Open the door on the main control box. Using a volt meter set on DC scale, check the DC voltage on terminal 4 (FTS NO) on the P2
connector plug in reference to any terminal 9, 12, or 14 on this same plug (refer to electrical schematics). The meter should read 0 DC
volts. If not, remove electrical power to the machine and recheck the wiring connections on the foot switch limit switch contacts to the
P2 connector plug.
The ‘com’ terminal on the foot switch limit switch must be wired to terminal 3 on P2 connector (FTS COM), the NO contact on the foot
switch limit switch must be wired to terminal 4 on P2 connector (FTS NO). The NC contact on this limit switch must be wired to terminal
5 on P2 connector (FTS NC). Verify that the wiring from the air valve is connected to terminals 12 and 13 on P2 connector.
Turn on the electrical power again (do not actuate the foot switch). Does the air cylinder still travel to bottom of stroke? If YES, check the
voltage on terminals 12 and 13 on P2 connector. The meter should read 0 DC volts. If the meter reads 0 DC volts, replace the electrical
air-solenoid valve in the drop-probe assembly.
SYMPTOM 3
After turning on the electrical power and air supply, the sensing probe does not go to bottom of stroke when the foot switch is actuated.
SOLUTION
Before proceeding, verify SYMPTOMS 1 and 2 are not the cause of this problem. Open the door on the control box. Actuate the foot
switch to the middle position if the machine has a two-stage operation, or all the way down for single-stage operation. Check the DC
voltage on terminal 12 and 13 on P2 connector. The meter should read +24 volts DC. If the meter reads +24 volts DC, turn off electrical
power to the machine and check the wiring again or replace the air-solenoid valve in the drop-probe assembly.
