THC301d Operation Manual

Jan 25 2010

First download and install Mach3 on your computer. Note: You will need to re-boot your

computer if this is the first time installing the Mach3 software. Download the THC300

install program from www.soundlogicUS.com It includes the THC301d profile.

Follow the instructions below.

1. Copy your license file into the Mach3 folder.

2. Run the THC-300 install program. It will copy all the files where they need to be for

the THC300 as well as the THC301d.

3. From your desktop, double-click the “Mach3 Loader” icon, and select the THC301d

profile.

4. Up at the top of the screen there is a menu called “Config”, select it.

5. Select the “Ports & Pins” tab.

The first box that comes up has a DRO (Digital Read Out) for the primary and secondary

parallel port address.

6. Enable Port 2 and enter your parallel port #2 address. Note: Do not enter the “0x”

preceding your port address as Mach will append this to your address value. If you need

help obtaining your secondary parallel port address, more information can be found in the

Mach3 documentation.

7. Click on “Apply” to save your changes, and then click on the “Inputs” tab.

8. Scroll down to the “EStop” setting and temporarily set it to “Active Low” for test

purposes and be sure to click the “Apply” button. Note: Make sure you change it back to

“Active High” before using the THC301d or it will not reset.

9. Exit the “Ports and Pins” dialog box.

10. Click on the flashing “Reset” button in Mach. It will stop blinking red and green and

will be a solid green.

THC301d

- For the first time user –

The next thing is to bench test the THC301d

.

Set the THC301d on a table close to your computer.

Connect the DB9 cable to the DB9 female mounted on the back of the cabinet.

Connect the other end to the sensor board.

Connect the parallel port the DB25 Female on the back of the cabinet.

Connect the other end to the second parallel port on your computer.

Note: Before connecting power; make sure the power jumper is set for the correct voltage

either 115 or 230 vac. This is done using J9 on the THC301d board in the cabinet.

Move both jumpers to either the 115 side or the 230 side.

Plug the power cable in and turn on the power switch located on the back of the cabinet

above the power cord.

With Mach3 running click on the Reset (solid Green) button on the lower left corner of

the main screen. The Green Ready LED will light on the front panel of the THC301d.

And the set volts will display on the meter.

You can adjust the set volts using the coarse and fine controls.

Click on the “Torch ON” button the Mach3 screen. You will hear a relay on the sensor

board click ; the voltage will be the same but you can’t adjust it. As soon you get an ARC

OK signal the meter will switch to read the Tip Volts. You can try this by placing a

jumper across J4 and J5 on the sensor board. You will see the Arc OK led on the sensor

board, the front panel and on the Mach3 run screen. The voltage will read 0.

Hall Effect Current Sensor ( HECS ) at the bottom

The above top photo is of the new HF sensor. The HECS current sensor located at the

bottom of the photo; is used to generate the Arc OK signal. To adjust it plug the HECS

cable into J14, plug the DB9 cable into the THC301d and the sensor board; turn the

power on to the THC301d, adjust the trim pot CW until the green LED lights then adjust

it back CCW until it just goes out.

You are now ready to install the THC301d on your plasma table. We have not tested the

Tip voltage inputs (J3 and J7). You will need to connect to the plasma machine to test

this (unless you have access to a variable 0 to 125vdc power supply).

More details will be covered in the installation of the sensor board in the plasma machine.

Connecting the Sensor board to the plasma machine.

The power supply on the plasma machine is a constant current supply. If you have it set

for 60 amps the supply will lower or raise the tip voltage enough to cause 60 amps to

flow through the torch tip through the metal to be cut and back to the power supply

terminal through the table ground cable. The amount of voltage it takes to make 60 amps

flow varies with the distance from the metal you are cutting. The THC monitors the tip

voltage to determine which way to move the z axis (torch) to maintain the set voltage, if

the tip voltage gets greater than the set voltage then Mach will move the torch down until

it is back at the set voltage. If it is less than the set voltage then Mach will move the torch

up until the voltage is back to the set point. The set point is adjusted with the coarse and

fine controls on the front panel of the THC301d.

All connections to the sensor board are non-polarized with the exception of J14 which is

keyed and J12 & J13. See Voltage divider below.

The tip voltage is monitored through the sensor board. J3 and J7 have a 6.5:1 voltage

divider and filter before being applied to the logic board.

You can mount the sensor board inside the plasma cabinet or in a small box and keep it

near the plasma machine. Locate J3 and J7 on the sensor board. They are to be connected

to the torch or tip volts inside the plasma machine. One lead will be connected to the Tip

Volts the other to the Table ground cable. Warning the tip volts can be as

high as 300volts DC when the torch is fired but not cutting. Use 16

gauge twisted wire with insulation rating of no less than 600volts to make the

connections. You will need the manual on your plasma machine to locate the RAW TIP

VOLTS terminal in the plasma machine as well as the table ground cable terminal in the

plasma machine. Make the connections.

Next we will connect the Torch ON or trigger wires used to fire the torch.

You will again need to refer to the manual to locate the terminals in the plasma unit.

Connect J10 and J11 on the sensor board using 16 gauge twisted pair wire here as well.

For the Arc OK signal you can use a dry contact ( relay contacts) out of the plasma

machine, if it has one, and connect it to J4 and J5

If you do not have an Arc OK signal, Arc Transfer, or Ready TO Move signal; we have

that covered later on as well.

HECS sensor below the Sensor board

We provide a Hall Effect Current Sensor (HECS) to generate the Arc OK signal. It

monitors the current in the work clamp cable from the plasma machine to the work. It is a

small ferrite bead; normally used as a filter; it is split and mounted in a plastic holding

clamp. The clamp will have a Yellow dot on one end. Clamp it around the work clamp

cable with the yellow dot on the end toward the work clamp. It will sense current from 10

amps to 100 amps plus.

To adjust:

With the plasma machine off; plug the HECS cable into the HECS and J14 on the sensor

board apply power to the THC301d with the sensor board connected. The LED should be

out. Adjust the small trim pot CW until the LED comes on. Then adjust it CCW until it

just goes out; then adjust ¼ turn more.

To test it; apply power to the plasma and fire the torch in the air; the LED should be out;

if not adjust the trim pot CCW until it is out. Then start a cut you get an Arc OK LED.

The Arc OK signal indicates when the torch is drawing current. Mach3 monitors this

signal and will not move the X and Y axis until it receives it. The exception is with the

TORCH ON button in Mach3 is toggled off then the X and Y will still move. You can

make an air cut with the Plasma off; for a test in this mode.

Voltage Divider Some of the newer plasma machines provide a voltage divider for the tip volts.

If you wish to use it you can move jumpers J8 and J9 to the extern + and – inputs on the

boards, open the THC301 cabinet and locate jumper J11 and place a shunt (Jumper)

across it. Note the photo below

Place a clip lead across J4 and J5, with the plasma off; fire the torch and adjust VR1 trim

pot inside the THC301d located close to J11 to 255 volts on the meter on the front panel.

Remove the clip lead from J4 and J5. Then connect the divided voltage from the plasma

to J12 + and J13 – observing the polarity.

It is best if you know your plasma has the voltage divider and you want to use it; let us

know when you order theTHC301d and we will set up and adjusted for you before

shipping. You cannot use the voltage divider with the THC300.

New Feature

This feature not needed in most types of cutting. If you cut very thin material

that warps easily or cut corrugated sheet metal it does improve the

performance by allowing the THC Rate to be increased.

Installing the new feature involves re-mapping the Z step and dir from port1

to port 2. The step and dir pins on port 2 are as follows; step is 4 and dir is 8.

Also involves some wiring changes. You need to make a 3 pin cable long

enough to reach the Z axis drive. See photo below. It is shown connected to

a Gecko drive step and dir signals. Pins 1,2,3 on the DB9 male are Pin 1

COM Pin 2 DIR and Pin 3 is step.

Note inside the THC301d the green slip on screw connector. And just to the

right of it; is a jumper. Make sure you set the jumper on the common to

either a gnd or +5v to match your drive.

Once the changes are made test the Z axis to make sure you can jog it up and

down . When you start a cut you can adjust the THC Rate up a little at a time

until you get some oscillations indicated by a vibration in the Z axis. Move it

back down a little and you should be good. Some customers have reported

increase in the THC Rate % as much as 10 percentage points like form 8 to

18. This will increase the Z velocity to allow cutting corrugated sheet metal.

If you can get the Z velocity = to the X/Y velocity you can cut up to 45 deg

angles. Because of the variations in the Zaxis, drives and reductions some

will get better results than other. However all that said the THC301d works

very well as it is out of the box.

Each unit is Bench tested and calibrated

The Floating Head

The best way to find the proper pierce height is to use a floating head on the Z axis. You

need SheetCam to generate the tool path to take advantage of the floating head.

A floating head is a torch mount with a linear bearing mounted vertically on the side

toward the Z axis mount. The Z axis mount has rail mounted vertically. The bottom edge

of the plate has a stop to prevent the floating mount from falling off the bottom side.

The floating head bearing is mounted on the rail from the top of the Z axis mount. It

freely slides down and rests on the stop. There is a switch mounted on the Z axis mount

that will turn on when the floating mount moves up a small amount. This switch is

connected to the breakout board Z home input. On the THC breakout board it connects to

port 1 pin 13, (Zhome). For noise it is best to use a normally closed (NC) switch. Make

sure you set the active level of the Z home input to active high for a normally closed

switch.

To test the THC301d with Mach reset ; set the fine control to mid range adjust the coarse

to the desired tip voltage. You can get this from the plasma user manual.

Run your Gcode .

You can tweak the voltage to the best cut if it is needed with the fine control.

With the fine control set at center. You can vary the voltage +- 5% of what the coarse

control is set for.

Below are the steps for a typical cut via a g-code file.

Load your g-code file into Mach.

Toggle the THC ON to ON in the Mach3 run screen.

Click the cycle start button in Mach3.

The X and Y axis will move to the first cut point.

The Z axis will move down (home down) and the torch will touch the metal, the axis will

continue moving down until the floating head hits the switch (Z home switch). The Z axis

will move up to the pierce height and the torch will fire. It will then wait until it gets the

Arc OK signal.

Mach will take control and move the X and Y axis to make the cut. As the tip voltage is

being monitored you should see the UP and Down LED’s flashing and you will see the

amount of correction that is made in the Zero THC DRO.

After the cut is finished, Mach will turn off the torch and also zero the Zero THC DRO.

Hypertherm 1250 Interface Locate J14(+work) and J17 (-Torch TIP) connect to J3 and J7 using a twisted pair wire 18 gauge with insulation of 600v. Locate J19 Connect J10 and J11 (torch ON ) to J19 pins 1 (white) and pin2(Red) Connect J3 and J4 (ArcOK sw) to J19 pins 3(Yellow) and pin4(Black) The drawing below is for the Hypertherm 1250. The drawing is located on the last page of the Hypertherm service manual. It can be downloaded from the Hypertherm web page library

Note 1

Noise is the worst enemy of electronics and a plasma machines generate a lot of it!

Proper grounding is very important.

Make sure you use a heavy copper grounding strap from the plasma chassis to a

grounding rod. Also ensure your ground rod is driven into the earth at least 3.5 to 4 ft.

Then wire another equally heavy ground strap from the table to the same grounding rod.

These need to be good connections so make sure to clean down to bare metal.

One test you can run is disconnect your computer and monitor power cords and with

everything else connected measure the resistance between the computer chassis (a screw

on the back of the case) and the table. It should be a high resistance ( a meg or so). Now

connect the computer and monitor back up and take the same measurement, it should a

low resistance (in the 100s). It varies due to ground conductivity.

We recommend shielded cable to the limit/home wiring and opto-isolators are used for

home and limit switches on our breakout board to help eliminate noise and voltage spikes

from getting to the computer.

It is further worth noting that the THC-300 has opto-isolators on all of the inputs and

outputs.

Typical setting for 16 ga steel.

Powermax 1000

Fine cut consumables

Cut height .06

Pierce height .12

Air pressure of 65

30 amps

CV stop CV on angles 90

THC plasma mode OFF

Enable Enhanced Pulsing