The G200 command is used to define the operating parameters for plasma cutting.

When placed at the start of a G-code file, the G200 command populates the Plasma Parameters tab on the F2 screen with the specified values.

To access the Plasma screen, Tool 112 must be selected. This can be done by entering T112 M6 in MDI. It is considered best practice to include T112 M6 near the start of plasma G-code files.

Syntax & Parameters

The G200 command uses its parameters to populate the Plasma Parameters tab

• The F value defines the touch-off feed rate used during probing.
• The P value defines the piercing height, which is the height the torch moves to before piercing begins.

• The D value defines the piercing delay and is specified in milliseconds.

• The C value defines the cutting height, which is the height the torch moves to after piercing is complete.

• The V value defines the cutting voltage. If this value is set to 0, MASSO enters Auto Voltage mode, where the voltage is sampled at cutting height and then maintained for the remainder of the cut. Use of this parameter requires the MASSO DTHC module.

• The A value defines the anti-dive feed rate percentage. This parameter has not yet been implemented and will be added in a future release.

• The O value controls Ohmic probing, where 0 disables Ohmic probing and 1 enables Ohmic probing

• The S value controls whether the system stops after piercing and waits for Cycle Start. A value of 0 disables this behaviour, and a value of 1 enables it.

Example Program

N10 G200 F150 P5.5 D500 C3.1 V116 A50 O1 S0

This example defines all plasma operating parameters using the G200 command.

Understanding G200 Operation

The G200 command defines how the plasma system operates.

Issuing G200 with no parameters disables G200 operation and places the plasma system into legacy mode, where all plasma operations must be manually controlled using G-code.

By default, G200 is enabled when MASSO powers on. If older plasma files are being run that rely on legacy behaviour, a G200 command with no parameters should be added at the start of the file to disable G200. This can also be done through MDI, but adding it to the file is recommended.

Once G200 is turned off, it remains disabled until it is re-enabled or MASSO is repowered.

G200 can be used with external THC units, such as the Proma 150, and is mandatory when using the MASSO DTHC module.

When G200 is active, many plasma operations are automated, significantly simplifying the required G-code.

Automatic Plasma Start Sequence

When G200 is active and an M3 command is issued, MASSO performs the following sequence automatically.

Probing begins using the F value as the probing feed rate. Once touch-off is detected, the torch height is set.

The torch then moves automatically to the piercing height defined by the P value.

The plasma arc is started.

When the Arc OK signal is received, the piercing delay timer defined by the D value begins.

At the end of the piercing delay, the torch automatically moves to the cutting height defined by the C value, and cutting begins.

Parameter Details

F – Touch-Off Feed Rate

This value defines the feed rate used during automatic probing when G200 is active.

P – Piercing Height

This defines the Piercing Height used as part of G200 when it is active.

It is the height the torch will move to perform the piercing.

D – Piercing Delay

This value defines how long the torch waits after piercing before moving to cutting height. The value is specified in milliseconds, where a value of 2000 represents 2 seconds.

C – Cutting Height

This value defines the height the torch moves to after piercing is complete.

V – Cutting Voltage

This value defines the voltage used by the MASSO DTHC to control torch height during cutting. If a voltage is specified, MASSO maintains that voltage during cutting.

The voltage can be adjusted in real time using the Torch Up and Torch Down buttons on the F2 screen  

Each press adjusts the voltage by one volt. A new voltage value can also be entered directly into the Cutting Voltage field on the Plasma tab.

If the V value is set to 0, MASSO uses Auto Voltage mode and samples the voltage at cutting height for each cut.

A – Anti-Dive

This parameter is not currently implemented. When available, it will define a feed rate percentage below which the Z axis locks to prevent the torch from diving into the material, which commonly occurs during arc cutting.

O – Ohmic Touch-Off

This parameter controls which touch-off method is used.

When O0 is set, the Plasma Touch input is used. This typically involves a physical switch in the torch that activates when the torch contacts the material surface. In this mode, the Torch Touch Offset value is used to calculate torch height.

When O1 is set, the Plasma Ohmic input is used. This method detects contact through an electrical connection between the torch tip and the material. Ohmic touch-off does not use an offset value.

Both touch-off methods can be configured, but only one can be active at a time. Ohmic mode is active when the on-screen Ohmic button is yellow.

S – Stop After Piercing

When piercing thick material, molten metal can build up on the surface, creating a risk of the torch colliding with the material.

When S1 is set and an M3 command is issued, the torch touches off, moves to piercing height, and performs the piercing delay. The plasma then turns off and the torch retracts to the Z home position.

The operator can clean the material surface, and once ready, press Cycle Start. The torch then rapids to cutting height, the plasma starts, and cutting begins.

This sequence occurs on each M3 command.

When S0 is set, the system transitions directly from piercing to cutting height with no pause.

The default value for S is 0 at power-up, and the last S value is remembered until it is changed or MASSO is repowered.

Build up left after piercing thick material