TCS2-CONVEYOR Troubleshooting

This topic lists problems that can arise with a tunnel conveyor and how to address them. This topic applies to the Tunnel Control Station 2 (TCS2).

Conveyor starts unexpectedly

1.          Check to see if the conveyor is forced on in Device Overrides.

a.        At the TunnelWatch computer, click Overrides.

b.       Locate the CONVEYOR device in the device list.

c.        Verify the CONVEYOR device is set to AUTO.

d.       If the CONVEYOR is set to Force On, click AUTO to change.

Conveyor stops unexpectedly / when washing cars

A Stop switch is a piece of hardware that signals the conveyor to stop running. Some Stop switches, such as Stop buttons or floor switches, are manual. Some sites have automatic Stop switches programmed to stop the conveyor when a certain condition is present - such as low air or low hydraulic fluid in the conveyor hydraulic power pack.

1.          Check the Conveyor Enable Circuit.

a.        Go to the TCS.

b.       Find the conveyor enable circuit in the upper right side of the TCS box.

c.        All four LEDs should be on.

i.           If none are on, the 24 VAC control power is interrupted somewhere.

●          Check the breaker.

●          Check the outlet to which this power supply is connected.

●          Check the wiring of the conveyor enable circuit NEUT and PWR terminals.

●          Ensure that your 24VAC power supply is wired properly according to the instructions in the Tunnel Control Station Installation guide.

ii.         If JUST the 24V LED (the first LED) is lit, first check the fuse on the board. If the fuse is good, or if you replace the fuse and it immediately blows again, one of the stop switches or the associated wiring is broken/open.

iii.       If just the 24V and STOP LEDs (the first two LEDs) are lit, press a start switch again. If nothing happens, the start switch or its associated wiring is broken/open.

d.       Check the conveyor enable circuit input light. This is usually the green input C light on input card number 1.

i.           If the conveyor enable LED is lit, the problem probably lies in TunnelWatch or a tripped circuit breaker. Proceed to step 2.

ii.         If the conveyor enable LED is not lit, the problem probably lies in the Stop/Start buttons of the Conveyor Enable Relay.

●          Check the lights on the Conveyor Enable Logic Board.

o          If ALL of the following are ON, continue to step 2:

■          Green 24V LED

■          STOP LED

■          ILOCK LED

■          Input LED for the conveyor enable circuit on the Input Card (typically Input C)

o          If the green 24V LED is OFF, check the fuse (SC0014) on the board or site-supplied 24v power supply.

o          If the green STOP LED is OFF, the stop circuit is open (stop button is pressed, loose connection, etc):

■          Check the Start/Stop buttons again. Take the cover off of each one and make sure the wires are attached and not corroded. Also, make sure there is no moisture in the Stop/Start buttons.

■          Check the fluid levels in the Conveyor Hydraulic Power Pack. Electricians will sometimes wire the fluid level switches so that they act like a Stop button, making the "CONV. ENABLE" indicator light go out when they are tripped.

o          If the yellow ILOCK LED is ON and the LED on the Input Card is not lit, check the wiring from the conveyor enable logic board to the input board. The connector is labeled "TO TCS INPUT" and typically connected to 1C and COMM.

o          If the yellow ILOCK LED is OFF, press a start button. If the light remains off, replace the relay on the Conveyor Enable Logic Board (RE02412).

2.        Check the tunnel exit to determine whether the collision avoidance system has been triggered.

3.        Verify that the computer doesn't have power management turned on.

a.        Computers ship from DRB Systems with Power Management turned off. To verify this, see the Hardware Help topic for the specific model of computer in use at the site.

4.       If the conveyor shuts down and the cars that were in the tunnel stay in the TunnelWatch queue, then try to restart the conveyor.  If the conveyor won’t restart immediately, then check the oil level of the conveyor hydraulic pack and also the temperature sensor of the hydraulic pack if it is equipped with one.

5.        If none of these solutions work, move on to the "Conveyor won't start" section below.

Conveyor won't start

These steps apply to the older-style TCS - the one without the tablet display. After each of the steps in this section, try pressing a start button to determine whether the conveyor is working again.

Note: The conveyor does not auto-start at the beginning of the day. TunnelWatch only auto-starts the conveyor if it auto-stopped it. You must press a stop button and then press start again to get the auto-start to begin its normal process.

1.          Check the Conveyor Enable Circuit, if you haven't already.

a.  Go to the TCS.

b.  Find the conveyor enable circuit in the upper right side of the TCS box.

c.  All four LEDs should be on.

i.  If none are on, the 24 VAC control power is interrupted somewhere.

●   Check the breaker.

●   Check the outlet to which this power supply is connected.

●   Check the wiring of the conveyor enable circuit NEUT and PWR terminals.

●   Ensure that your 24VAC power supply is wired properly according to the instructions in the Tunnel Control Station Installation guide.

ii.  If JUST the 24V LED (the first LED) is lit, first check the fuse on the board. If the fuse is good, or if you replace the fuse and it immediately blows again, one of the stop switches or the associated wiring is broken/open.

iii.  If just the 24V and STOP LEDs (the first two LEDs) are lit, press a start switch again. If nothing happens, the start switch or its associated wiring is broken/open.

d.  Check the conveyor enable circuit input light. This is usually the green input C light on input card number 1.

i.  If the conveyor enable LED is lit, the problem probably lies in TunnelWatch or a tripped circuit breaker. Proceed to step 2.

ii.  If the conveyor enable LED is not lit, the problem probably lies in the Stop/Start buttons of the Conveyor Enable Relay.

●   Check the lights on the Conveyor Enable Logic Board.

o  If ALL of the following are ON, continue to step 2:

Green 24V LED

STOP LED

ILOCK LED

Input LED for the conveyor enable circuit on the Input Card (typically Input C)

o  If the green 24V LED is OFF, check the fuse (SC0014) on the board or site-supplied 24v power supply.

o  If the green STOP LED is OFF, the stop circuit is open (stop button is pressed, loose connection, etc):

■    Check the Start/Stop buttons again. Take the cover off of each one and make sure the wires are attached and not corroded. Also, make sure there is no moisture in the Stop/Start buttons.

■    Check the fluid levels in the Conveyor Hydraulic Power Pack. Electricians will sometimes wire the fluid level switches so that they act like a Stop button, making the "CONV. ENABLE" indicator light go out when they are tripped.

o  If the yellow ILOCK LED is ON and the LED on the Input Card is not lit, check the wiring from the conveyor enable logic board to the input board. The connector is labeled "TO TCS INPUT" and typically connected to 1C and COMM.

o  If the yellow ILOCK LED is OFF, press a start button. If the light remains off, replace the relay on the Conveyor Enable Logic Board (RE02412).

2.        Check the Messages section of the Quick Status screen to determine whether there's any error condition present. If so, check the "TunnelWatch Error Messages" topic and follow the steps to resolving the issue that triggered the message.

3.        Check the stop buttons to make sure none of them are stuck.

a.        Press a stop then a start button for the conveyor in your tunnel.

b.       Reprogram the vehicle and try again.

c.        Press all stop buttons, then press a start button for the conveyor. This is to verify that none of the stop buttons is stuck.

4.       Check for jammed rollers. A jammed roller can cause the conveyor to stop sending a pulse.

5.        Check and reset your circuit breakers.

6.        Check the fluid level switches. Some sites have their conveyor set up so that it does not run when one or more fluid is low.

7.        Use the red power switch on the TCS power supply to turn the TCS off. Wait 30 seconds, then turn it back on.

8.        Force the conveyor on from the TCS.

a.        Determine which relay the conveyor is connected to (typically 1A).

b.       Move the switch to the ON position.

c.        The green LED lights up when the toggle switch is closed.

i.           If the conveyor starts, move the switch back to AUTO and continue to step 3.

ii.         If both LEDs do not turn on, check TCS power and swap the relay board with a board from another slot.

iii.       If they conveyor does not start, the issue is typically outside of the TunnelWatch system. For instance, wiring, hydraulic fluid, air compressor, circuit breaker, conveyor motor, conveyor starter, or non-standard circuitry.

9.        Verify communications with the TCS.

a.        Go to the TunnelWatch computer and log in to TunnelWatch.

b.       Click Operations. The Operations screen appears.

c.        In the TCS Status section, check the Success percentage. If any station has a Success percentage of less than 95%, use the "Tunnel Control Station Communication Troubleshooting" document in the old TunnelWatch Help to determine why communications aren't happening and to address the issue.

10.     If all stations are 95% or above, verify the conveyor enable input in TunnelWatch.

a.        From the TunnelWatch computer, click Setup. The Setup screen appears.

b.       Click Tunnel Related Inputs. The Tunnel Related Inputs screen appears.

c.        Click the Conveyor tab. The Conveyor screen appears.

d.       Verify that the Box, Input, and Switch Type options match the actual TCS location of the Conveyor Enable circuit. For instance, if the Conveyor Enable relay is in the first TCS, using input 1C, and is normally closed, then the settings should match those pictured at the bottom of this page. Note: The Conveyor Enable Circuit should always be set to Normally Closed.

e.        If the conditions inside the TCS don't match the configuration in TunnelWatch, change the configuration in TunnelWatch.

11.        Force on the conveyor from TunnelWatch.

a.        Click Overrides. The Overrides screen appears.

b.       Locate the conveyor device, and click Force On next to it.

i.           If they conveyor does not start, set it back to Auto On and continue to the next step.

ii.         If the conveyor starts, set it back to Auto On.

12.      Check the setup of the conveyor relay.

a.        Click Setup. The Setup screen appear.

b.       Click Conveyor, Idle and Horn. The Conveyor, Idle, and Horn Control screen appears.

c.        Verify that the Box/Relay fields match the box and relay number on the TCS (typically Box 1 Relay 1A).

d.       Make any changes needed, then save.

Conveyor doesn't stop when stop button is pressed

1.          Determine whether the conveyor is forced on in TunnelWatch.

a.        Go to the TunnelWatch computer.

b.       Near the top of the screen, click Overrides. The Overrides screen appears.

c.        In the Device Overrides section, locate the Conveyor option and check whether the Force On button is selected (blue). If so, click the AUTO button, then check to see whether the stop button works.

2.        Verify the Conveyor input settings.

a.        In TunnelWatch, click Setup. The TunnelWatch Setup and Configuration screen appears.

b.       Click Tunnel Related Inputs. The Tunnel Related Inputs screen appears.

c.        Click the Conveyor tab.

d.       Record the Box/Input and Switch Type values.

e.        Verify that those values match the settings on the Conveyor Enable Circuit inside the TCS.

3.        Try the all the other stop buttons to determine whether the problem is limited to one button.

a.        If the problem is NOT limited to one stop button, skip to step 4.

b.       Check the yellow ILOCK LED on the Conveyor Enable Relay.

i.           Go to the TCS and locate the Conveyor Enable Relay.

ii.         Have someone push and release the stop button. The yellow ILOCK LED should turn off and stay off.

●          If the yellow ILOCK LED doesn't turn off, the TCS is not receiving signals from the stop button. Troubleshoot the wiring to the button, and then check the button hardware itself.  

●          If the yellow ILOCK LED turns off when the button is pushed but comes back on as soon as it is released:

o          If the yellow ILOCK LED turns off when any stop button is pushed but comes back on as soon as it is released, there may be a bad or shorted start button, or the start button wiring is malfunctioning. Troubleshoot the button hardware and wiring.

o          If the button hardware and wiring are fine, there may be a problem with the conveyor enable circuit board. See "Conveyor Enable Test Troubleshooting Issues" topic in the old TW Help (90149-1106).  

4.       If all of the stop switches fail to turn off the yellow ILOCK LED:

a.        Check to see if the green STOP LED goes out when all Stop buttons are pushed.

b.       If the green STOP LED does not go out:

i.           The Stop button wiring is the problem.

ii.         See "TunnelWatch Tunnel Control Station Installation and Wiring" in the old TunnelWatch Help (90361-1106) for more information.

c.        If the green STOP LED does go out and the yellow ILOCK LED still does not go out.

i.           The conveyor enable relay may be at fault.

●          Remove the conveyor enable relay.

●          If the yellow ILOCK LED still does not go out:

o          Disconnect the wires to the CONV and INTLK terminals on the Conveyor Enable circuit board.

o          If the yellow ILOCK LED goes out:

■          The problem is the Conveyor Enable Circuit wiring.

■          Most likely, there is a 24v source connected to one of these terminals.

o          If the yellow ILOCK LED still does not go out, it is possible that the Conveyor Enable circuit board is bad.

o          If the yellow ILOCK LED goes out, replace the conveyor enable relay.

5.        If the ILOCK and STOP LEDs operate properly when the Stop and Start buttons are used, but the conveyor still does not stop.

a.        Remove the Conveyor Enable Relay.

b.       If the conveyor still runs:

i.           The problem is in the conveyor motor, starter, or other external wiring.

c.        If the conveyor stops, replace the Conveyor Enable Relay (RE2412).

Conveyor enable test troubleshooting

1.          Turn the Conveyor Relay (1A) in the TCS box to the OFF position.

2.        If the Green 24v LED is OFF.

a.        Check the 5-Ampere fuse on the Conveyor Enable board.

i.           If it is blown, replace it.

ii.         If it blows again, a short circuit exists in the Stop, Start, or conveyor wiring.

b.       Check to make sure the 24VAC Power Supply is on.

i.           Check the breaker or the outlet this power supply is connected to.

c.        Check the wiring of the Conveyor Enable Circuit NEUT and PWR terminals.

i.           Ensure that your 24VAC power supply is wired properly.

3.        If the Green STOP LED is OFF.

a.        If the green STOP LED is not on and the green 24V LED is on:

i.           Check the Stop switches and wiring.

Bypassing a Non Functioning Stop (Use With Caution)

Sometimes a stop input can be triggered when there is no issue with the offending stop itself.  In these situations, first validate the offending stop is functioning properly in the case of a low air/oil pressure switch, you do not want to operate the tunnel if either of these faults are indicating an actual issue with the pressure.

In the case of a stuck stop button, troubleshooting should be performed on the button itself by manually removing the cover of the button and inspecting the wiring for anything loose/corroded.  If the button cannot be unstuck, note to your staff that the button is non functional and proceed with the following steps to get the site back up and running.   Note: In either a faulty switch or a stuck stop button, notify a member of IT or Maintenance team right away to fix the issue and notify all staff of the issue and how to maintain a safely operating tunnel.

• Understanding the stop circuit and troubleshooting a stopped conveyor when no Stop lights are indicated.

  • Input wires are connected to the enable circuit to cut power to the conveyor when an emergency condition is met such as lower oil or a stop button.  Usually the offending stop is indicated on the conveyor board and facilities/IT can troubleshoot the direct cause or operations can add oil to the reservoir to clear a low oil issue for example.

  • Sometimes no indicator is lit but 24VAC is lit on the power supply but the interlock light is not lit up on the conveyor control board.  To troubleshoot this you may be asked to ‘jumper’ the stops to figure out which is the problem.

  • A ‘jumper’ wire requires either a small piece of wire with exposed ends or something small and metallic like a paper clip.  

  • Locate the stop circuit on the right side of the TCS main board, you will be able to see small letters indicating STOPS 1-8 next to the sections of green plastic ‘phoenix connectors’.  Each stop has an in and an out, so there are two contacts for each stop with the same label, i.e. you will see STOP 1 on two different contacts on the block.

  • With the guidance of IT or a facilities tech begin jumping the STOPS one pair at a time to see if the interlock light comes back on as indicated in the illustration below:

Additional Pictures