Hyd-Mech S-20 A Manual Download

Page: 50 / 80

3.12

LIDVSHFL¿FLQSXWOLJKWGRHVQRWFRPHRQZKHQH[SHFWHG

check for a faulty/misadjusted limit switch, push button, encoder or by faulty wiring and connections

wiring for each limit switch should be connected from the VDC terminal connection to particular limit switch, and
from the limit switch to the input connector of the PLC

NOTE: All inputs are denoted by “X”

All outputs are denoted by “Y”

Following is information on output diagnosis and the sequence of inputs and outputs during AUTO cycle.

AUTO CYCLE SEQUENCE
After changing to AUTO MODE and 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. Shuttle vise should open and

come forward to the home position. HUP input light must come on for cycle to continue. HUP Input ON – cycle
should continue. If not, check outputs as per step 2. HUP Input NOT ON – check that head up limit switch is being
actuated. Check limit switch/limit switch wiring.

2. Front vise should be closed, the shuttle vise should stay open and move back to the programmed length; FVC

output should be on SVO output will light momentarily. REV output and FST output should be on when the shuttle
moves back fast.

3. As the shuttle approaches target length the FST output should shut off and the shuttle should travel slow for the

DECELERATION DISTANCE Parameter, cushion distance (i.e. 1.00”). When the shuttle reaches target length, the
SVC output should light, and the shuttle vise should close on the material.

4. FVO output light should come momentarily on and front vise should open
5. FWD output should light as well as 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

the head should start to descend for the cut. If blade is not running at this time, auto cycle will hold until min. 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

head should move up. When the head reaches its up limit, HUP input should come on, RHD output off and the cy-
cle repeats with the next length being clamped on by the shuttle, front vise opening and the length being brought
forward to home position.

As mentioned, beside each input and output terminal there is a bank of red LEDs. Each light corresponds to its input or

RXWSXW$QLQSXW/('ZLOOOLJKWZKHQLWVVSHFL¿FLQSXWVLJQDOLVEHLQJUHFHLYHGDWWKH3/&DQGRXWSXW/('VZLOOOLJKWZKHQ
WKH3/&FRPPDQGVVSHFL¿FRXWSXWV,IDQRXWSXW/('LVRQEXWWKHRXWSXWGRHVQRWKDSSHQFKHFNIRUYROWDJHDWWKHVSH

FL¿FRXWSXWZLUH,IYROWDJHLVQRWSUHVHQWWKHQHLWKHUWKHRXWSXWUHOD\LVIDXOW\VWXFNRUWKHRXWSXWDPSIXVHKDVEORZQ

(See fuse information on the next page). If a fuse is blown, a shorted directional valve coil (good coil should measure 30
to 40 ohms), shorted noise suppressor at the coil, or shorted wiring could be the cause. If the fuse is good and no output
voltage condition still exists, with the output light on, then the relay is defective. If this is the case, the PLC will have to be
returned to the manufacturer for repair. (Contact Hyd-Mech Group Limited Service Dept.)

FUSES

The PLC has four glass fuses in line with it.
Fuse “4FU” is a 2-amp instant blow fuse, which feeds power to the input side of the PLC and operator interface terminal.
5FU1 is wired to terminal “V0” supplying Outputs – Y0, Y1, Y2, Y3, Y4, Y5, Y6
5FU2 is wired to terminal “V1” supplying Outputs – Y10, Y11, Y12, Y13, Y14, Y15, Y16
6FU supplying power to solenoids valves

PROBLEM #4 – NO DISPLAY

POSSIBLE CAUSES:
No power to the PLC
PLC unit failure
Faulty connection of cable between PLC & Interface