Hyd-Mech H18A-120, Руководство пользователя

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3.11
Problem #3
Auto Cycle Not Being Completed
In auto mode, the PLC controls the saw functions through output relays. For a certain function to be actuated, the PLC
must first see specific input(s). Like the output relays, the input relays are located on the PLC unit. Directly beside the
input and output terminals are red LED’s (Light Emitting Diode), which will light up when the corresponding input is being
received or output being actuated. Observation of these input/output LED’s can help diagnose auto cycle problems. Refer
to the PLC inputs and outputs in this section. When a problem occurs in the auto mode, the lights should be checked to
see if they are coming on at the proper time or if they are coming on at all.
Input LED’s
If a specific input light does not come on when expected
• Check for a faulty/misadjusted limit switch, push button, encoder or faulty wiring or connections.
• Wiring for each limit switch should be connected from the VDC terminal connection to the particular limit switch,
and from the limit switch to the input connector of the PLC.
Note:
All inputs are denoted by an “X”
All outputs are denoted by a “Y”
The following is information on output diagnosis and the sequence of inputs and outputs during the auto cycle.
Auto Cycle Sequence:
After the mode push button is in the auto position, the job has been programmed into the PLC, and the cycle start push
button pressed:
1. Hydraulics running, the head should move to its up limit if it is not already there. The shuttle vise should open and
come forward to the home position. HUP input light must come on for the cycle to continue.
a. HUP input on – cycle should continue, if not check outputs per step 2.
b. HUP input not on – Check that the head up limit switch is being activated. Check the limit switch/limit switch
wiring.
2. Front vise should be closed; the shuttle vise should stay open and move back to the programmed length.
a. FVC output should be on and SVO output will light momentarily, REV output and FST output should be on when
the shuttle moves back fast.
3. As the shuttle approaches the target length the FST output should shut off and the shuttle should travel slowly for the
DEC DIST parameter (cushion distance). When the shuttle reaches the target length the SVC output should light and the
shuttle vise should close on the material.
4. FVO output light should momentarily turn on and the front vise should open.
5. FWD output should light as will the FST for the shuttle to move forward in fast speed. FST will turn off when the
shuttle home cushion period is reached and the shuttle should slow down into the home position.
6. FVC output should light and the front vise should close. FWD light should go out, HDN output should come on and
the head should start to descend for the cut. If the blade is not running at this time, the cycle will hold until minimum SFM
is reached. Depending on “HLD SHTL HM” parameter in the PLC, the shuttle may stay home and closed during the cut or
may move back to pick up the next length. HUP input should go out as the head descends and HUP L/S deactivates.
7. After the cut is completed HDN input should light, HDN output should go out, the HUP output should light and the
head should move up. When the head reaches it’s up limit, HUP input should come on, HUP output should turn off, and
the cycle repeats with the next length being clamped by the shuttle, the front vise opening and the material being brought
forward to the home position.