FREQUENTLY ASKED QUESTIONS

What is the history behind MOBI-ARC?

MOBI-ARC is a product conceived, engineered, manufactured, and marketed by Mobile Welding and Power, Inc.  Over the last forty years, leaps in technology have afforded better, smaller, faster, and more reliable products.  After years of intense market analysis, MWP came to the conclusion that the alternator actuated welding technology hadn't stayed in stride.  Several products in the marketplace still utilized capacitor multiplier systems, multiple-switch operation, and inefficient and unreliable switching mechanisms.  Others required the purchase of a secondary alternator, cleverly dubbed a "power generator," or were sold at such an astronomical price-point, few could afford the unreliable and dated technology.  Installations were cumbersome, complicated, and downright user unfriendly.  MWP decided to change all of that.  A rigorous talent search yielded engineers qualified for the task at hand:  design a sold-state welding and power generation product that can run from a vehicle's stock alternator.  Make it small, make it easy to install, and do so at an affordable price.  It took engineers who specialize in sophisticated power management and switching over a year to design the MOBI-ARC product line.  It has been worth the wait!

WELDER EVOLUTION

Home Grown Welder conceived in the 1960's Instructions on the internet  connectors, solenoid,  resistor,  #4 cable, alternator dedicated alternator full-fielded for unregulated welding amperage alternator dependant open circuit voltage unregulated, can achieve 70 volts or greater Commentary:  rudimentary, inexpensive but time- consuming to build, will eventually burn out the alternator. Open circuit voltage outside UL guidelines and can generate heart-stopping voltage.
Premier Power Welder, Link-Arc Welder, Resco Welder, Thunderbolt Welder designed approximately 1971 sold under private label agreements using the names above, no discernable difference between the units Resco unit believed to be dead Premier/Link-Arc merged Thunderbolt (Canadian version of the unit) no longer manufactured, manufacturing entity purchases MOBI-ARC Control Units to satisfy customer base a more refined version of the "home grown" welder improvements include a purpose-built cabinet, an external regulator enabling the alternator output to be regulated for 14.5 volt battery charging, a 120v socket employing a capacitor multiplier system for the same, starter solenoid to isolate battery from unregulated welding voltage, analog gauge Commentary:  A step in the right direction.  Still quite rudimentary but suffers from design complications that could not be overcome with 1970's technology.  Ironically, the technology is available today, but the manufacturer doesn't employ solid-state circuits or conform to contemporary Electrical Engineering standards.  System works by sending a "less-than-battery" signal to the regulator. This turns on the field transistor allowing rotor to draw maximum field current and creating unregulated voltage and rpm-dependant amperage.  Vehicle's battery and electrical system isolated by the starter solenoid. Open circuit voltage outside UL guidelines and can generate heart-stopping voltage.
MOBI-WELD designed in 1987 in South Africa much more refined that the units above designed by an electrical engineer improvements include the use of a rotary-cam switch which avoided the "solenoid welded stuck" condition on predecessor units, employed a printed circuit board for some control, regulation, feedback, and safety, used transformers instead of the capacitor multiplier system Commentary:  A big jump in technology ushering in the use of a PCB and sound electrical engineering practices.  Break-before-make rotary-cam switch served the same functions of the solenoid, without the requirement to "throttle down" in order to avoid the solenoid-welding-shut- under-load issue.  Use of transformers instead of capacitors allowed for higher wattage output and overcame the inherent problem of  capacitors overheating due to alternator ripple-current.  System works by sending a "less-than-battery" signal to the regulator. This turns on the field transistor allowing rotor to draw maximum field current and creating unregulated voltage and rpm-dependant amperage.  Vehicle's battery & electrical system isolated by rotary-cam switch.
MOBI-ARC Designed, engineered, and manufactured in 2002 by Mobile Welding & Power, Inc. San Diego, CA CAD designed packaging State-of-the-art PCB assembly No moving parts for unparalleled longevity.  Your cell phone has no moving parts.  Nor your television, nor your Casio watch.  Why should your on-board welder?   Very simply: moving parts wear out and eventually need to be replaced.  A reduction in moving parts is universally accepted as a means of increasing product longevity and reliability. Solid-state circuitry creates no broadband noise or interference with automotive electronics.   Pulse-width Modulation Regulator implementing regulation technology designed for future 42 volt electrical systems currently in the auto industry pipe-line.  PWM is more efficient than transistor regulation.  Whereas transistor regulation turns field current all on or all off, PWM varies the percentage of "on" time about 100,000 times per second.  In practical terms, take two identical alternators: one transistor regulated the other PWM regulated.  The PWM regulated alternator will generate more current and in doing so, the PWM regulator will stay much cooler relative to the transistor regulator.  As we all know, things that stay cool last longer.   Automatic switching between "welding" and "charging" modes.  Want to weld?  Simply plug in the leads and go to it.  No switches to throw.  No solenoids to slap around.  MOS-FET's  switch and isolate current, thus allowing higher voltage output from the alternator, without compromising the vehicle's battery and electrical system. 50 second timer resets while welding.  Should welding cease for any 50 second period of time, MOBI-ARC will automatically resume charging the vehicle's battery at 14.5 volts. Customer safety, vehicle safety, and the integrity of our products are of paramount importance.  Our products generate virtually no heat.  Solid-state electronics yield the highest probability of trouble-free use.  A faulty unit or a high-resistance connection will likely yield heat as a symptom of a fault.  Should the temperature rise above specified parameters, the control unit will shut down and illuminate an "over temperature" LED.   100% duty cycle, over temperature will only occur due to a fault MODE SELECT Modules allow alternator output voltage programmable from 12 to 42 volts for jump-starting and assorted specialty applications. ISO9000 Certified wiring and cabling kits included with Each MOBI-ARC  meets or exceeds world-wide industry standards. MOLEX connectors have been chosen for making wire connections.  MOLEX designs and manufactures many OEM vehicular designed connectors found on most vehicles. Flexibility is critical.  MOBI-ARC wiring and cabling quick-disconnects off the back of the control unit.  With a secondary installation bracket and wiring/cabling kit, in less than two minutes, MOBI-ARC can be transferred between vehicles. Universal.  Any monkey can make an alternator weld.  Any monkey can make a purpose-built control unit that will make a specific alternator weld.  It takes insight and well-honed engineering skills to create a control unit that can connect to, and control the myriad of alternator configurations in the marketplace.  "A" and "B" circuit regulators.  Internal regulators, external regulators, computer controlled regulators.  This one needs a stator input, than one needs a tachometer output!!!!  It makes your head spin.  We've designed a control unit to give customers what they value most: choices.  Use your stock alternator, use a custom $200 alternator, use a a $1000 alternator.  The choice is yours. Scaled.  MOBI-ARC is available at several different performance levels and price points to meet any budget.   Expandable.  For those who require a 120 volt (or 220v) power outlet. MOBI-ARC can be connected to an accessory control unit called MOBI-POWER.  MOBI-POWER houses transformers and control technology allowing customers to power lighting and power-tools in the field.  Two versions will be available: a 2,500 watt unit with smaller packaging, and a 5,000 watt unit with larger packaging.  MOBI-POWER can be hard-mounted, or simply connected when power is required.	PCB automated assembly machine eliminates human errors.
	One of three testing stations.
	Assembly
	MOBI-ARC 300 i-Series Industrial
	MOBI-ARC 200x
	MOBI-ARC 130

What is the welding amperage and duty cycle of MOBI-ARC?

All MOBI Control Units are designed to run at 100% duty cycle.  The   alternator is the amperage base and is designed to cool efficiently while creating continuous current.  Welding amperage is strictly a function of the size of the alternator.  If you are using MOBI-ARC with a 90 amp alternator, you will have 90 to 100 amps of welding current at your disposal.  If you have a 250 amp alternator, you'll have 250 to 260 amps at your disposal.  Keep in mind that alternators are designed for continuous duty.  Whether it's charging your vehicle's battery, or welding, alternators are designed for one purpose: generate current on a continuous basis and cool efficiently while doing so.  Our state-of-the-art regulation system will  allow 5% to 15% better output from any given alternator, but there's no magic involved; simply a more precise and efficient way to control and regulate alternator output.

What type of welding electrodes work best for general-purpose use?

Many of our clients utilize a 6011 ac/dc welding electrode in sizes ranging from 3/32 up to 5/32 on our larger systems. 6011and 6013 rods are very forgiving in terms of ease of use and is the best “all-around” rod for clients who never know what they’re going to come up against (rust, powder-coating, paint, etc... ). Many of our clients utilize a 7018 rod in similar sizes. For the novice, 7018 is a stickier rod to weld and is thus more difficult use. It has a higher tensile strength (70,000 psi) than the 6011 (60,000 psi) but in most cases, 60,000 psi is stronger than the parent metal anyway. Basically, the welding rod you choose depends on two things; your application and your personal preference. For your convenience, we sell a welding rod starter kit which includes samples of popular size rods, sealed canister, gloves, etc.

What length welding cables can be used?

Because MOBI-ARC Units are PWM regulated and powered by an alternator, the DC current's frequency is higher than that of a conventional welder. Consequently, the #4 welding cables can be longer than the typical stationary welder, however, you cannot defy the laws of physics.  The longer the cables, the higher the resistance.  Customers usually select 30 foot welding leads for general use.  Cables longer than 70 feet, a larger cable size should be used.  Due to the weight involved, welding leads are typically not provided with our kits, however they can added for your convenience.  Welding cables can also be purchase from your local MOBI-ARC representative, local welding supply store, or through the following mail-order suppliers:

www.delcity.net   

  www.waytekwire.com  

Does the vehicle's original alternator have to be replaced?

MOBI-ARC is unique in that it can be used in conjunction with most original alternators.  It can also be used in conjunction with aftermarket, high-output, and custom alternators.  Flexibility is the name of the game.

Will the MOBI-ARC void my vehicle's warranty?

Short answer----NO.   Long answer....keep reading.  How many times have you heard someone at a dealership say that installing aftermarket equipment automatically voids the warranty?  This common misconception has been repeated often enough to be widely believed – though it is completely false.  Most vehicle owners are not aware they are protected by federal law: the Magnuson-Moss Warranty – Federal Trade Commission Improvement Act of 1975. Under the Magnuson-Moss Act, aftermarket equipment does not void a vehicle manufacturer’s original warranty, unless the warranty clearly and conspicuously states that aftermarket equipment voids the warranty.  Most states have warranty statutes that provide further protections for vehicle owners.  In other words, that means a dealer can’t wiggle out of his legal warranty obligation merely because you install aftermarket equipment.   A dealer must prove – not just say – that aftermarket equipment caused the need for repairs before he can deny warranty coverage on that basis.  .

What RPM must the engine run in order use the MOBI-ARC?

The alternator reaches maximum output at approximately 6,000 alternator rpm's. The MOBI-ARC system generates constant current / constant voltage and the alternator need not spin 6,000 rpm's for welding output; generally between 4,000 and 6,000 alternator rpm's achieve quality welds. Generally, this equates to 2,000 engine rpm's, assuming a three-to-one pulley ratio.  To translate alternator rpm's to engine rpm's, use the following equation:

Circumference = 3.14 x diameter (of the drive surface)

a) Assuming a 2" alternator pulley, circumference = 6.28

b) Divide drive diameter of main crankshaft pulley by 6.28

c) Divide result of (b) into 6,000 to find engine revs required to produce approximate maximum welding output.

TIG welding can be facilitated at much lower RPM's than stick welding. In most cases, TIG welding can be done at idle, or just hair above idle whereas stick welding requires more current due to the resistance of the welding electrode.

How do I know if the alternator on my vehicle is okay for use with the MOBI-ARC System?

The MOBI-ARC Control Unit is designed to work in conjunction with most alternators.  The alternator can't use avalanche diodes in the rectifier.  Avalanche diodes are designed to conduct at +/- 25v and the welding process requires higher voltage. Does the alternator on your vehicle generate the amount of amperage necessary to meet your welding needs?  We've welded with alternators as small as 55 amp and as large as 300 amps.  Like all moving parts, alternators wear out over time.  It's important that your alternator be in good condition.  Was your alternator built with top-quality components?  If it's a "high-output" alternator, did the manufacturer accommodate for appropriate heat dissipation?  When it comes to alternators, as the saying goes, "you get what you pay for."  If you purchased your alternator at auto parts store #4126 and paid $18.00 and got a life-time warranty, one might not expect the quality and durability to be stellar.  We encourage clients to purchase quality alternators from reputable rebuilders and manufacturers.  Most clients will find the stock alternator on their vehicle to be of acceptable size and quality.  If you have reservations, ask your MOBI Reseller for advice.

Can I choose a larger alternator for my vehicle?

You certainly can.  The beauty of MOBI-ARC is you can use any alternator you choose.  Our advice: choose the highest amperage alternator you can afford and the easiest to install.  Physical space on your vehicle may prohibit installing a larger alternator. Favorable alternator clocking and/or dimensions may not be available. 

If my vehicle already has a good alternator, do I have to buy a "MOBI"  alternator?

Absolutely not!  Keep in mind that the folks who tell you that you must have a special "welding" alternator are the same people who are trying to sell you an expensive alternator as part of their kit.  They supply the alternator for two reasons: ability to separate you from more of your money, and their control unit lacks the flexibility and sophistication to control the numerous alternator configurations found in the marketplace.  Most customers use their stock alternator and are very pleased with its performance.  If the stock alternator is too small, then the purchase of a larger alternator will yield more welding flexibility.    

Is it possible to buy the alternator already prepared to connect to the control unit?

Absolutely. You can purchase the alternator from us, or we've established relationships with alternator manufacturers and rebuilders across the country.    

Can I transfer one control unit from vehicle to vehicle?

Yes, it's possible to transfer the control unit between vehicles. This is a feature you'll find unique to MOBI-ARC.  All installation wiring terminates at the back of the control unit allowing for easy installation and removal.  As we don't modify the charging system, the stock alternator can charge properly without the control box being present.

What changes are made to the alternator?

With any given alternator, we look at three items: regulator configuration, diode trio situation, and avalanche diodes.  With most alternators, no changes are necessary which makes MOBI-ARC plug-n-play.  If the alternator has a diode trio, it must be disabled; most alternators don't use a diode trio.  We disable the regulator, but we disable it in such a way that restoration can be facilitated by a provided mating plug.  We can't have two regulators fighting for control.  On the welding side, the preferred stator winding is a delta configuration.  A delta wound stator is not imperative, but it will tailor the alternator's performance toward welding.  In star configuration (aka wye), the alternator will put out higher voltage at lower engine revs, but at the expense of the amperage at higher engine revs. In delta configuration, the alternator will put out slightly lower voltage at lower engine revs (idle), and 34% more amperage at higher engine revs. Most passenger vehicles have alternators in star, most big-rig trucks and diesels utilize delta configuration. It simply changes the performance characteristics of the alternator depending on the application, without compromising the reliability. For maximum welding output, delta configuration is ideal. For 120v power output, star configuration is ideal.

Will the alternator deteriorate with excessive use as a welder?

No, if the alternator is of decent quality, the unit will be able to maintain welding current without complications.  Alternators are designed for continuous output and alternators don't know if they're charging a dead battery, or welding.  In terms of its performance, it's all the same.

 

What is the difference between the MOBI-ARC and the 110v power module?

Aside from the standard charging of the vehicle's electrical system, the MOBI-ARC has two functions: a D.C. high-frequency welding output, and battery jump-starting and boost-charging ability. The 110v power module is an accessory control unit that connects to the MOBI-ARC and provides a 120 volt D.C. power outlet (220v and 240v available with foreign outlets). The 110v power module is not yet available.

How is the MOBI-ARC system different than other welders on the market?

The MOBI-ARC Control Units contain a surface-mount printed circuit board (PCB) that acts as the brain. The PCB houses a pulse-width modulation (PWM) control circuit that controls the alternator more efficiently than a traditional transistor-based regulation system (PWM is utilized in all computer power supplies, automotive cell-phone chargers, and literally thousands of other products where power must be controlled).  The PCB also houses numerous control, switching, and safety circuits specifically designed to provide the most sophisticated, yet most reliable control unit on the market.  Our control units have no switches that the operator must toggle.  All functions are voltage-sensing and completely automatic.  MOBI-ARC blends a unique mix of technologies to bring our customers unparalleled performance and safety.

In our 110v power module, transformers allow us to take current from a standard alternator and utilize it in a rectified DC format to drive a 1,500 to 5,000 watt load. This transformer technology is patented worldwide and is far more efficient than the capacitor multiplier technology used by other alternator actuated systems on the market. Dual Mode Operation (welder and 120v outlet) means one can idle the vehicle up, weld and/or use the 120 volt outlet, without having to return to the vehicle to manipulate multiple toggle switches. Other systems use a starter solenoid in conjunction with multiple toggle switches to change from one mode to another. This type of technology needs a reduction in rpm and load prior to mode switching or the solenoid may stick and doesn't allow the use of the 120 volt outlet while in the "welding" mode and visa versa. In practical terms, this means that when using other systems, the user switches into the "weld" mode, switches "Hi/Low" to "Hi," idles the vehicle up, welds, idles the vehicle down, switches into the "120 volt" mode, idles the vehicle up, grinds, idles the vehicle down, switch "Hi/Low" to "Low," and switch into "Charge" mode. Whew! Conversely, the MOBI-ARC is completely automatic.

 

What is meant by "solid-state" technology?

Solid-state technology is the use of a printed circuit board to perform functions traditionally carried out mechanically. The reduction in moving parts is universally accepted as a means of increasing the longevity and reliability of the product.

What is wrong with the capacitor multiplier technology used by other systems?

Simply put, the capacitors cannot take the ripple current generated by the alternator. Regardless of size or quality, the capacitors will get hot  quickly, and we all know what heat does to products. Voltage doubling capacitors have the highest failure rate of any electronic component in history. MOBI-ARC's 110v power module uses transformers that don't don't suffer like the capacitor multiplier method.  Our competitors use capacitors which are electronic components that are designed to absorb a charge and release it very quickly. Unfortunately, they cycle a limited number of times, heat up extraordinarily quickly, and are guaranteed to eventually fail. For example, using a 200 amp alternator, other systems generate 2300 watts of 110 volt DC at 80% duty cycle. This means one can use power tools or lights eight out of every ten minutes; two minutes of cooling time are necessary so the capacitors don't pop. Conversely, the 110v power module, with its transformer technology, using an 100 amp alternator, can generate 5,000 watts of 120 volt DC at 100% duty cycle. The transformers don't suffer from heat problems, last indefinitely, and are more efficient than capacitor multiplier technology. Patents were acquired worldwide on the step up transformer technology and is unique to MOBI-ARC's 110v power module

Can I transfer one control unit from vehicle to vehicle?

Yes, with quick-disconnects, it's possible to transfer the control unit between vehicles. Being internally or externally regulated, your alternator can work properly without the control unit being present.

Is the control unit water resistant?

The MOBI-ARC Control Unit is water resistant, but not sealed. We Krylon coat the printed circuit board (PCB) in a clear plastic coating to insure that, if water gets inside the control unit, it will not short across the PCB.  For a nominal fee, dielectric gel can be applied for additional protection.  Many people ask why we don't epoxy the board?  The PCB is a substantial percentage of unit's cost.  Once epoxy is applied, individual parts on the board cannot be accessed.  In the event of a component failure, the entire PCB would have to be discarded.  Dielectric gel provides equal protection, but it's permeable should testing or repair be necessary. The transformers are not affected by water. The control unit is designed to be placed in the engine compartment and can withstand heat, vibration, and water from engine cleanings, rain, etc.

What type of equipment can MOBI-ARC 110v Module run?

MOBI-ARC 110v Module generates 120 volts DC which means it can run any universal motor (any motor that has carbon brushes). Such tools include grinders, drills, saws, sanders, impacts, heaters, coffeepots, blenders, hot plates, halogen lights, incandescent lights, and air compressors with universal motors (Sears Craftsman #15234 with the 1.5 HP).

What devices cannot be run by MOBI-ARC's 110v Module

Anything with capacitors and/or induction motors. Such devices include computers, televisions, radios, fluorescent lights, pumps, and most compressors.

Will I be stranded if the control unit stops working?

No, you will not be stranded. With a bolt and a Bypass Plug supplied in the emergency bypass kit, the alternator will charge the battery as normal.

What do the LED lights indicate?

• Weld  Light illuminates when control unit is in "welding" mode.
• Ignition  Light illuminates when keyed-on 12 volts (ignition) is switched on.
• Charge   Light illuminates when the alternator is connected to  the vehicle's battery.
• OverTemp Light illuminates when the temperature within the control unit exceeds specified parameters.

Can the power outlet voltage be configured for different countries?

If volume justifies, then yes. The transformers dictate the voltage output from the power outlet. Units are pre-configured prior to shipment and comply with whatever voltage output is necessary (120v/220v/240v)

 

 

1	Why do I need to run an isolator in a multi-battery configuration?
2	Why do I need an isolator that performs at peak efficiency?
3	What makes POWER-GATE isolators different than traditional silicon and Schottky packages often found on boats and RV's?
4	What makes POWER-GATE isolators different than other MOSFET isolators?
5	Can POWER-GATE devices be used on 12 volt and 24 volt electrical systems?
6	What's the difference between a POWER-GATE relay and POWER-GATE switch?

 

Why do I need to run an isolator in a multi-battery configuration? Battery isolators are a necessary part of high-reliability multi-battery systems. They're used to isolate batteries so a failure of one battery won't bring down the battery network. In the case of RV's, boats, and other recreational activities, it is prudent to have engine starting batteries isolated from accessory and/or house batteries, thus avoiding being stranded without the ability to start the vehicle. If the battery network is all tied together and being used as one big battery bank, an battery internal short or an accessory accidentally left on can drain all batteries.

Why do I need an isolator that performs at peak efficiency? Conservation of power. The vehicle's engine is converting liquid gasoline into mechanical energy to turn the crank shaft. The crank pulley spins a belt across the alternator pulley where the alternator turns mechanical energy into electrical energy. This DC electricity is transferred to battery(s) through cables, switches, and isolators where the energy is stored and used by the vehicle. Every watt that's thrown away as resistance and dissipated as heat must be generated by the alternator. If the electrical system requires 100 amps at 14 volts, and the isolator is throwing away 8 amps, the alternator must generate 108 amps to break even. Choosing an isolator that performs at peak efficiency saves fuel, saves wear-and-tear on alternators, belts, and pulleys. With less wasted energy being dissipated as heat, components run cooler and better. Using an inefficient, sloppy, bulky, energy-wasting isolator is penny-wise and pound-foolish.

What makes POWER-GATE isolators different than traditional silicon and Schottky packages often found on boats and RV's? Commonly know as "diode isolators," traditional methods of isolating current have been superceded by the use of electronics know as MOSFET's. These devices have numerous qualities which make them vastly superior than traditional silicon and Schottky diodes. MOSFET's are now widely used in low power applications while POWER-GATE uses a newly patented manufacturing process which allows MOSFET's to be deployed in high-current applications. The inherent nature of MOSFET's makes them dramatically more efficient than predecessor solid state methods of isolating power.

What makes POWER-GATE isolators different than other MOSFET isolators? Unlike other MOSFET isolator, POWER-GATE is manufactured in a static-free clean room utilizing robotic assembly techniques. Our patented assembly process yields devices that achieve levels of efficiency that others strive (but fail) to achieve. POWER-GATE can handle large amounts of continuous power, and do so with such little wasted energy that it doesn't require heat sinks, thermal bonding, or airflow. While others measure resistance in milliohms (thousandths), we've jumped to the micro-ohm (millionths) world!

Can POWER-GATE devices be used on 12 volt and 24 volt electrical systems? POWER-GATE can be used on both 12 volt, and 24 volt electrical systems. Our in-house design team can also tailor units to work at other voltage levels as well. Please inquire for special applications.

What's the difference between a POWER-GATE relay and POWER-GATE switch? POWER-GATE relays and switches take the place of mechanical contactors, solenoids, and switches. When switching high current using mrchanical devices, an electrical arc is generated as the device opens and closes. This constant arcing becomes a high-resistance connection which ultimately generates so much heat that the switch fails. P-GATE serves the same function, but the high current flows through solid state electronics so there's no arc generated, no contact surfaces to deteriorate, no moving parts to wear out, and the amount of power needed to turn and hold the device "on" is a mere fraction of a conventional contactor. P-GATE relays are designed to be switches on-and-off remotely and P-GATE switches have an integrated switch built directly into the package so it can be switch on-and-off right at the P-GATE.

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