UB25 LINEAR DC RESISTANCE WELDING CONTROL
990-665
7-1
CHAPTER 7
CALIBRATION
Section I. Introduction
Overview
Calibration instructions are displayed on the series of screens displayed on the Power Supplies LCD.
There are only two Calibrations
setups
, or equipment connections. After you connect the Power Supply
to the calibration equipment as instructed, follow the instructions shown on each LCD screen. While
some of the instructions may appear slightly different, the procedures are essentially the same.
It takes approximately one hour to calibrate the Power Supply if working by yourself, faster with an
assistant. Once you are familiar with the calibration process, it will become faster and easier to do.
After performing these procedures, the Power Supply will store the calibration values in RAM, where they
will be used as standards for the operational welding parameters.
NOTE:
Only authorized personnel should perform this procedure.
Calibration Equipment Required
This equipment is required for calibration:
•
2 weld cables, No. 2/0, 1 ft (30 cm) long (Pt # 2/0 BB12)
•
4,000 micro-ohm coaxial shunt resistor accurate to ± 0.5%.
Source for shunt resistor ( Model K-1000-2, 150 Watts, Mod 0.004 ):
T & M Research Products, Inc.
139 Rhode Island Street NE
Albuquerque, New Mexico 87108
Telephone:
E-Mail:
(505) 268-0316
www.tandmresearch.com
•
Calibration Kit, Pt # 4-35914-01
−
Filter Assembly (Pt # 4-36835-01)
−
Special Calibration Cable, (Pt # 4-35913-01)
−
Standard BNC Cable (Pt # 205-157)
−
BNC "T-Connector" (Pt # 250-486)
•
Digital oscilloscope, Tektronix 724C or equivalent
•
2-wire, normally open switch for weld initiation, mating connector (Pt # 520-001)
The waveforms displayed on the oscilloscope screen will vary from pulse to pulse. To calibrate the Power
Supply, adjust the energy output to the
average
value of each pulse displayed on the oscilloscope.
