High Frequency Inverter Power Supply - HF27, HF25


  • Real Time Feedback
  • Displacement and force monitoring
  • Force control
  • Envelope function
  • Combo mode
  • Energy and time limits


Miniature welds are highly sensitive to even the smallest heat profile fluctuations during the resistance welding process:  overheating deforms and destroys parts, while under heating results in a weak, unacceptable bond.  
Precisely controlled heating, therefore, is required to achieve consistent, reliable welds.
The HF27 high frequency inverter welding machine achieves this level of control by precisely managing and monitoring both electrical AND mechanical weld parameters in a completely closed-loop process. 
Perfect for automation.  Can address a wide range of applications including sensitive medical device components, solar cells, automotive electronics, battery tabs, battery pack assembly and more!


Specification :

Model Number







Nominal Line Voltage (3 phase)

240 VAC

400 VAC

480 VAC

240 VAC

400 VAC

480 VAC

Line Voltage Range (VAC)

192 to 264

320 to 440

384 to 528

192 to 264

320 to 440

384 to 528

Input Circuit Rating (per phase)







Input KVA @ 3% duty cycle


Output KW @ Max. demand


Output Transformer Voltage @ Max. Rated Output Current


Open Circuit Max. Output Voltage @ Nominal Line


Setting Ranges

Current – 100A to 2400A; Voltage – 0.2V to 10V; Power – 50W to 10kW

Output Current

2400A @ 3% duty cycle

Output Feedback Response Time (Current, Voltage, Power)

40 Microseconds

Output Regulation versus Line Voltage Variance


Output Regulation versus Load Resistance Variance


Output Repeatability Current, Voltage, Power ± of Setting


Weld Period Ranges

All segments except squeeze and hold 0.10ms to 10ms, 0.1ms steps; 10 to 99ms, 1ms steps; squeeze and hold 0 to 999ms, 1ms steps

Weld Energy Setting Accuracy

Current: 2% of setting or 2A, whichever is greater; Voltage: 2% of setting or 0.050V, whichever is greater; Power: 5% of setting or 20W, whichever is greater


Features :

Weld Heat Profile Functions

Weld Pulse Control

Dual pulse with independent control of current, voltage, power or combo mode (HF27) on each pulse.

Programmable Weld Pulse Segments

Squeeze, upslope 1, weld 1, downslope  1, cool, upslope 2, weld 2, downslope  2, hold.

Weld Schedule Memory

Save up to 100 different  weld schedules, protected from unauthorized changes.

Measurement Parameters

Independent monitor of current, voltage, power, and resistance on each pulse. Envelope, time limits and energy monitor (HF27).

Graphic Display

Back-lit LCD displays programmed  and actual weld current, voltage or power, upper and lower limits, and resistance.

Measurement Selection

Peak or average

Current Measurement Range/Accuracy

50.0A to 2.400KA/± 2% of reading or ± 2A, whichever is greater.

Voltage Measurement Range/Accuracy

0.2V to 9.999V/± 2% of reading or ± 0.05V, whichever is greater.

Power Measurement Range/Accuracy

0.01KW to 9.999KW/± 5% of reading or ± 20W, whichever is greater.


Display alert, four user programmable AC/DC relays; audio alarm.

Programmable Weld Energy Limit

Terminates weld energy when exceeding user defined current, voltage, or power limits.

Weld Pre-Check

Inhibit second weld pulse when first test pulse exceeds user programmed limits.

Active Part Conditioner

First pulse current limit in constant power allows second pulse to fire.

I/O and Data Communications


Input Isolation

All inputs and outputs are fully isolated.


Selectable: + 5V, + 24V, sourcing or sinking inputs.

Firing Switch Initiation

1-level foot switch, 2-level foot switch, mechanical or opto firing switch.

Remote Control

Remote weld schedule select, process inhibit, emergency stop.


Change weld schedules and individual parameters.


Change weld schedules and individual weld parameters; “Daisy Chain” unit to unit, unit(s) to host computer.

Electrode Voltage


Weld voltage signal for voltage feedback operation (0 to 10V peak).

Weld Head Air Valve Driver

24 VAC, 1A; timing controlled by HF25/HF27. Operates new EZ-Air.

Alarm  Relays

Four user-programmable mechanical relays; programmable normally open or normally closed; contacts:
250 VAC at 5 A; 30 VDC at 5 A. Conditions:  weld, end of weld, alarm, out of limits.

Displacement Option (H F27 only)


Part detection, final thickness measurement, set down measurement, energy stop (weld to limit)

Accuracy of Displacement Readings Inches (mm)

± .003 (0.076)


± 1.0 %

Maximum  Travel Inches (mm)

1 (25)

Alarm  Relays

Additional conditions: Any LVDT, initial Lo/Hi, final Lo/Hi, displacement  Lo/Hi, initial NG, displacement  NG, energy stop

Data Output

Initial thickness, final thickness, displacement, and any alarm condition


Attaches to Miyachi Unitek Series 80 weld heads. Includes LVDT, interface cable, and mount

Force Controland M onitor (H F27 only)

Force Input

0-10V input signal from signal conditioner or load cell

Force Measurement

End of squeeze, end of hold

Force Output

0-10V for use with proportional valve

Force Programming

lbs, kg. N. force can be stored b schedule

Physical Characteristics

Dimensions (L x W x H) Inches (mm)

18 x 9 x 12.8 (460 x 230 x 325)

Weight – Lbs (Kg)

54 (25)


. 2013 (c) Kooner Technology (H.K.) Co., Ltd..