SECTION 4
OPERATION
This section provides descriptions of the power source controls and general oper-
ating procedures plus, some tips on cut quality.
CONTROLS AND INDICATORS
The status lights located on the front of the top lid of the ESP-150 console provide
the conditions of the circuitry during a normal plasma arc cutting operation. By
knowing the proper sequencing of events and by observing the status lights one
can troubleshoot the console in a short time to minimize downtime.
None of these lights will function unless proper input voltage is applied with the
links on the input terminal board (TB) properly connected for the input voltage; the
ON-OFF power switch is ON; and the top lid of the console is closed firmly.
The following are the functions of each control:
POWER (ROS) — Energizes power to the Fan, Water Cooler and Control Cir-
cuitry. This readies the unit for operation.
GAS MODE (OSS) — CUT - Allows for setup of cut gas pressure and flow; START/
SHIELD - allows setup of start and shield gas pressure and flow; and OPERATE -
position to use for cutting operations.
CURRENT CONTROL — Controls desired cutting current for optimizing speed
and cut thickness. See Application Data on pages 27 through 28.
OVER TEMP — Will light if any (one or more) thermal switch in the console is
open due to overheating. (This light may be dim when the gas flow is in the post-
flow mode.) If light comes on, stop cutting operations and allow unit to cool down
(with fan running) until light goes out. If the light is on and you suspect the unit is
cool, then check for defective thermal switch(es) or loose connections.
READY/LOW GAS — This light serves as a READY light, torch switch and oper-
ate/set switch check as well as low gas flow or pressure indicator. It will light when
the unit is at rest or READY (power ON-OFF switch is ON. It will continue to be lit
when operate/set switch (OSS) is placed in the SET position even when proper
gas flow or pressure is set properly. The light will not go out when the OSS switch
is placed in the OPERATE position (gas solenoid valves will shut off).
In the operate mode, this light will then function as a LOW GAS light. After
depressing the torch switch button and the LOW GAS lights up during a cutting
operation, gas pressure or flow is insufficient.
HIGH FREQ ENERGIZED — This will light when the unit is in the OPERATE mode
and the torch switch button is depressed. It should remain lit until the main cutting
arc is established. It indicates that proper voltage (approx. 115 VAC) is applied to
the primary of the high frequency transformer (HFTR). The voltage is applied to the
HFTR through proper operation of the pilot arc contactor (PAC).
TORCH ON — This will light when the power supply is delivering the voltage to
generate an arc (whether or not the main arc has been established). It is indicating
there is greater than 50 volts between NEG output and WORK terminals. Never
touch the front end parts or make any adjustments to the torch if the TORCH
ON light is on, even when the power ON-OFF is OFF.
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