【NEW】For DC spot welding/fusing: IS-300A

Compact and high power!
High quality fusing!NEW
Model : IS-300A

    • Compact and 1.5 times higher output than that of the conventional model IS-120B.
    • Detailed weld schedules can be set.
      Transformer selecting function
      • Six control types

        You can choose from; "Primary constant-current RMS," "Secondary constant-current RMS," "Secondary constant-power RMS," "Primary constant-current PEAK control," or "Constant-phase" to attain stable welding quality.
      • Different setting can be set at each welding.

        Pulsation, Upslope, Downslope and Weld stop.
      • Power supply voltage fluctuation compensation control (effective when PULSE LIMIT is set)

        The pulse limit is corrected according to the fluctuation in the power-supply voltage on the primary side.
        This function is valid only in the primary constant-current PEAK control mode (PLM).

    • Up to five transformers can be connected with IS-300A by an optional MA-650A the transformer selector.
      This function contributes to the improvement in productivity.
    • Interrupt feature
      Interrupt feature functions when a displacement amount reaches up to set level and stops current to obtain more stable fusing. For this feature, it needs to be connected with a weld checker with a built-in displacement monitor and set a displacement amount of electrodes beforehand.
    • Program unit MA-660A (Sold Separately)
      Employing an easily viewable color LCD. Current, voltage, or power can be monitored.
    • Multilingual software
      You can select the language from Japanese, English, Chinese, and Korean.
    • Samples


Model IS-300A-00-00 IS-300A-00-01
Power requirements (Fixed at ex-factory) 3-phase, 200–240 VAC
±10% (50/60 Hz)
3-phase, 380–480 VAC
±10% (50/60 Hz)
Max. output current 300A (Peak value)
Number of schedules 255
Output frequency 600Hz~3kHz (In 100 Hz increments)
Control method Primary constant-current RMS
Secondary constant-current RMS
Secondary constant-power RMS
Primary constant-current PEAK (with pulse width limit funcution)
Secondary constant-voltage RMS
Constant-phase control
Timer setting range   msec mode / cyc mode
SQUEEZE DELAY 0000~9999ms / 000~999cyc
SQUEEZE 0000~9999ms / 000~999cyc
UP SLOPE 1,2,3 000~999ms / 00~50cyc
WELD 1,2,3 000~999ms / 00~50cyc
DOWN SLOPE 1,2,3 000~999ms / 00~50cyc
COOL 1,2 000~999ms / 000~999cyc
HOLD 00000~20000ms / 000~999cyc
OFF *1 0 or 0010~9990ms / 00~99cyc
Transformer turns ratio 1.0~199.9
Pulsation setting 01~19
Valve setting 2
Setting range
(1)Constant current *2 (2)Constant power
(3)Constant voltage (4)Constant phase
(1)0.1~20.0kA (2)0.1~20.0kW
(3)0.20~9.99V (4)10.0~99.9%
Current monitor 00.0~99.9kA / 0.00~9.99kA
Power monitor 000.0~999.9kW / 00.00~99.99kW
Voltage monitor 0.00~9.99V
Pulse width monitor HIGH 10.0~100%
Cooling method Forced air-cooling
Data communication RS-232C (One-way communication) /
RS-485 (Bidirectional communication)
Operating environment Ambient temperature +5~+40℃
Humidity 90% max. (no condensation)
Altitude 1000m max.
Weight 16.5kg
  • *1: No repetitive operation will be performed if “0” is selected for OFF (off time).
  • *2: Primary current can be set up to 300 A.


Model ITH-651C6W ITI-875A6W SIT-F241-HC
Rated capacity 26.8kVA 37.1kVA 75kVA (50%)
Rated primary voltage 300V/600V 300V
No-load secondary voltage 9.3V 12.5V 11.7V
Transformer turns ratio 32:1/64:1 24:1/48:1 24:1
Input frequency 1kHz
Maximum welding current 7000A 7000A 14400A
Duty cycle 8.5% 9% 10%
Fan voltage DC24V
Cooling method Forced air-cooled
Weight 16kg 19kg 35kg
Outline dimensions (mm) * 168(W) x 398(D) x 199(H) 168(W) x 446(D) x 199(H) 180(W) x 495(D) x 240(H)

* Include projections