Technical_reference - 第131页
Technical Service Manual 131 Revision Dat e: August 2004 4. T urn the bottom potentiom eter (one) on the PLC ½ turn clock wise. T ouch and hold the fr ee end of the test wire to the IN 2 term inal on the PLC. Verify that…
Technical Service Manual 130 Revision Date: August 2004
Procedure for Stand-alone SMEMA Machine Interface Test
Required Equipment:
Pre-programmed PLC - Vitronics Soltec part number 1476902
3 wire "cheater cord" - power cord with stripped back wires on one end and a plug for a 115 Volt outlet on the other
10 jumper wires (24 to 16 AWG) each approximately 4 inches long.
Small screwdriver (flat or phillips) for adjusting the trim potentiometers.
The SMEMA operation of each lane is independent in the PLC. Each lane can be tested separately or together without
effecting the other.
1) Connect the following jumper wires: From 24VDC to COM 0 and to COM 1 terminals on the PLC. From 24 COM to I
3 to I 6 and then to I 7 on the PLC. Connect one additional test wire on the PLC from the 24 COM terminal and leave
the other end unconnected (not touching anything).
2) Connect the 3 wire cheater cord to the power terminals: green or green/yellow to the protective earth ground, white
or light blue to neutral ( NEUT ), and the remaining wire (typically red, black, or brown) to the "hot" or "line" terminal (
L1 ).
3) Plug the cheater cord into a standard 115 Volt outlet. The lights on the PLC should flash for a few seconds, while the
PLC is running self-diagnostics. The "power" and "run" lights on the front of the PLC should remain on.
Lane 1 Testing
4) OUT 0 on the PLC should be on to indicate that the oven is ready to accept product from the upstream machine lane
1.
5) Turn the top potentiometer (zero) on the PLC fully counter clockwise for minimum product spacing. The
potentiometers on the Allen Bradley PLC are located behind a removable access plate on the front lower left of the
PLC below the Allen Bradley logo.
6) Touch and hold the free end of the test wire to the IN 1 terminal on the PLC. Verify that OUT 0 goes off on the PLC
while the test wire is connected to IN 1 and remains off for an additional second after the test wire is moved off of the
IN 1 terminal.
7) Turn the top potentiometer (zero) on the PLC ½ turn clockwise. Touch and hold the free end of the test wire to the IN
1 terminal on the PLC. Verify that OUT 0 remains off approximately 30 seconds after the test wire is moved off of the
IN 1 terminal.
8) Return the top potentiometer (zero) on the PLC to the fully counter-clockwise setting.
9) Temporarily disconnect the wire(s) connected to terminal I 6 on the PLC. Verify that after 30 seconds OUT 0 is off on
the PLC to indicate that the oven is no longer ready to accept product on lane #1.
10) Touch and hold the free end of the test wire to terminal I 4 on the PLC and verify that OUT 2 on the PLC comes on
and remains on until the test wire is removed to indicate that product is available to a downstream machine.
Lane 2 Testing
1. OUT 1 on the PLC should be on to indicate that the oven is ready to accept product from the upstream machine lane
2.
2. Turn the bottom potentiometer (one) on the PLC fully counter clockwise for minimum product spacing. The
potentiometers on the Allen Bradley PLC are located behind a removable access plate on the front lower left of the
PLC below the Allen Bradley logo.
3. Touch and hold the free end of the test wire to the IN 2 terminal on the PLC. Verify that OUT 1 goes off on the PLC
while the test wire is connected to IN 2 and remains off for an additional second after the test wire is moved off of the
IN 2 terminal.
Technical Service Manual 131 Revision Date: August 2004
4. Turn the bottom potentiometer (one) on the PLC ½ turn clockwise. Touch and hold the free end of the test wire to the
IN 2 terminal on the PLC. Verify that OUT 1 remains off approximately 30 seconds after the test wire is moved off of
the IN 2 terminal.
5. Return the bottom potentiometer (one) on the PLC to the fully counter-clockwise setting.
6. Temporarily disconnect the wire(s) connected to terminal I 7 on the PLC. Verify that after 30 seconds OUT 1 is off on
the PLC to indicate that the oven is no longer ready to accept product on lane #2.
7. Touch and hold the free end of the test wire to terminal I 5 on the PLC and verify that OUT 4 on the PLC comes on
and remains on until the test wire is removed to indicate that product is available to a downstream machine.
8. Unplug the cheater cord and remove all of the connections to the PLC. Lightly tighten all the screws before returning
the unit to its box.
End of stand-alone test.
Technical Service Manual 132 Revision Date: August 2004
TEMPERATURE PROFILE PLOTTING (PRECISION PROFILING)
) Standard, (installed on all ovens) ! An option, (NOT installed on all ovens)
Plotting a temperature profile provides a graphic display of temperature relative to time and distance at one or more
points on a test PCB going through the oven. It also determines values of Peak Temperature, Liquidous Time and
Heat/Cool slope. This helps fine tune the system for optimization of individual profile parameters on the PCB.
Oven Profiling, Profile Objectives and Definitions, Preparing Thermocouples & PCBs, and Plotting a Temperature
Profile are described in Process Manual
.