Sunkko 737G+ User manual

Model: 737G+
Thank you for choosing Sunkko 737G+ battery spot welder, let's now make the building
of Lithium battery pack for our projects more convenient and efficient.
Manual

Summary
737G+ is a big improvement on the basis of 737G. It is specifically designed
for battery welding (18650, 14500 and any other lithium batteries, etc) and
can be used to weld nickel strips with thickness between 0.05 and 0.35 mm
for nickel plated steel or between 0.05 and 0.25 mm for pure nickel strip.
(Attention: When the foot pedal is plugged in, it’s in MT mode, otherwise, it’s
in AT mode.)
There are three ways of welding:
Fixed welding head with foot pedal: You can build your battery pack with the
fixed welding head and foot pedal. Coordinating hands and feet at the same time
will make the long-term welding process not so tiring, plus the use of foot pedal
during battery welding improves the precision of spot welding. In this welding
mode, you need to adjust the pressure adjustor to make the spots more reliable
and elegant.
Welding range: 0.15~0.35mm for nickel plated steel, 0.12~0.25mm for pure nickel
strip;
Preparation steps:
1. Fit the fixed welding head with copper welding rods before the machine
powers on.
2. Plug in foot pedal.
3. Turn on the main power button, and then the welding power switch.
4. Adjust the pulse quantity and welding current level to make the spots
more reliable and elegant.
5. Weld your batteries with fixed welding head along with the foot pedal.

Mobile welding pen with foot pedal(MT): The mobile welding pen effectively
extends your welding area, and this design is popular among electric hobbyist,
because they can build large lithium battery packs for their e-bikes or other
projects.
Welding range: 0.05~0.2mm for nickel plated steel, 0.05~0.15mm for pure nickel
strip;
Preparation steps:
1. Insert mobile welding pen.(In this case, do not fit welding head with
copper welding rods.)
2. Plug in foot pedal.
3. Turn on the main power button, and then the welding power switch.
4. Weld your batteries with mobile welding pen along with the foot pedal.
Mobile welding pen without foot pedal(AT): In this mode, you need to unplug
the foot pedal first. Once the welding pen attaches nickel strip, the welding pen
will release the energy and weld automatically, you just need to give a little
pressure to the pen just like you are writing.
Welding range: 0.05~0.2mm for nickel plated steel, 0.05~0.15mm for pure nickel
strip;
Preparation steps:
1. Insert mobile welding pen. (In this case, do not fit welding head with
copper welding rods.)
2. Turn on the main power switch, and then turn on the welding power
button.
3. Adjust the pulse quantity and welding current level to make the spots
more reliable and elegant.
4. Weld your batteries with mobile welding pen.
(Attention: In all the steps mentioned above, please make sure that the
copper welding rods of the fixed head and the welding pins of the mobile
welding pen are not in contact with each other to avoid short circuit. When
users need to adjust the distance between welding pins on mobile welding
pen or distance between copper welding rods of fixed head, please turn off
the welder first, do not adjust the distance when the welder is on.)
In general, there are two methods to improve the output power of spot
welding: adjusting welding current level through current knob or adjusting
pulse quantity. You may need to play with them a bit to get the best
combination for your specific use.
How is the pressure knob works?
The pressure knob regulates the pressure between copper welding rods and
nickel strip. Generally speaking, the thinner the nickel strip, the smaller the
pressure. A proper pressure between nickel strip and welding rods can also
make the spots more elegant.

(Attention: This spot welder can be used to weld pure nickel, nickel plated
steel, nickel plated iron, iron and other alloys. It CANNOT weld metal like
copper and aluminum.)
Specification for welding part:
Input voltage: AC 110 V/220 V±10%
Welding current: 120 ~ 1200 A
Single pulse time: 5ms
Max. pulse quantity: 18
Max. power output: 4.3 KW (instantaneous)
Fixed welding part:
Welding thickness for nickel plated steel: 0.15 ~ 0.35 mm
Welding thickness for pure nickel: 0.12 ~ 0.25 mm
Mobile welding part:
Welding thickness for nickel plated steel: 0.05 ~ 0.2 mm
Welding thickness for pure nickel: 0.05 ~ 0.15 mm
Specification for mobile welding pen:
Welding needle distance (adjustable): 2 - 7 mm
Total length: approx. 22.8"
Cable cross sectional area: 16mm2
Dimension of welding pins: 1.5x7mm
Others
Product dimension: 14x25x20cm
Item weight: 7kg
Packing List:
737G+ main machine: 1 pc
S70BN mobile welding pen: 1pc
Copper welding rods: 2 pairs
Mini grinder with USB cable: 1pc
Copper welding pins for mobile pen: 1 pair
Battery fixture: 1 pc
Foot Pedal: 1 pc
Fuse: 2 pcs
Hexagon wrench: 1 pc
0.15 x 8 x 100 mm (nickel plated steel) 50 pcs
0.1 x 4 x 100 mm (nickel plated steel) 50 pcs
Manual: 1pc

Notice
1. When building battery pack with Sunkko welders, if the home circuit system keeps
tripping, please replace your Circuit Air Breaker. For 110V version machine, the Circuit
Air Breaker in your circuit system should be higher than 40 A. For 220V version
machine, the Circuit Air Breaker in your circuit system should be higher than 30 A.
2. Please put on gloves and mask during your battery pack welding process to protect
yourself (Sparks may occur during welding process).
3. Unplug the welder when you are not using the welder.
4. During your welding process, the instantaneous large current generated by the welder
may cause the lighting equipment under the same power system flash and it is
considered normal.
5. Do not short circuits during spot welding or charging.
6. Do not use Sunkko welders with a voltage transformer as Sunkko welders are not
compatible with the common voltage transformers in the market.
7. Continuously spot weld too fast will speed up the loss of internal components of the
spot welder. We recommend that the time between each spot welding should be 3
seconds or longer.
Warranty information
1. What is covered?
This limited warranty covers defects in main machine.
2. What is not covered?
The warranty does not cover any damage caused by the owner modifying,
attempting to fix, or otherwise altering the machine.
The consumable accessories are not in coverage, such as welding pen,
cooper rods and nickel strips.
3. How long does this coverage last?
The warranty lasts one year since the date of original purchase of the product.
4. Who is covered?
This limited warranty covers only the original purchaser of the product on
sunkko.net. If you need warranty service, please contact us at
[e-mail] directly and provide us your order ID.
If you still have questions on sunkko products, please go to the blog category
on https://www.sunkko.net/ or email [e-mail]. We are happy to
assist you.