5 minute fix of the day

[Jim Davey]

No catch, if it gets warm the fan comes on, if it cools down fan goes off. The only catch is that you need to find the part of the machine that gets hottest first. In an inverter it's the heatsink. In a transformer machine it's the centre of the tranny that usually gets hottest (it will retain heat for longer too because of the tightly packed windings and iron core retaining heat well) so if fan as needed is required then the temp switch is inserted into the inner part of the windings when the transformer is made. Rectifiers due to their aluminium plate design shed heat quickly so of you mount the temp switch on the rectifier it can get hot a lot slower than the tranny will, then rapidly cool after you stop leaving the transformer still roasting away.
You need to be sure to put the sensor in the right place and make sure it has good thermal contact with the parts you want kept cool.
No good having the switch right in the airflow but not having a good thermal connection to a heatsink as the switch itself will switch off leaving the heatsink still hot, that's why you use the heatsink compound.

 

[Richard.]

If there was no catch then the likes of RTech, gys, TA etc would fit that switch. They must know the roaring fans are annoying so if it makes no difference to the machine and it's capability then they would fit them in as standard.

 

[Jim Davey]

Why do you think that might be?

 

[Richard.]

Well I'm not an expert in the guts of a machine Jim and I know that you are so it's not a case of I know it's a case of why would those brands continue to hard wire those fans into the mains as it's clear owners hate it if it can be resolved with a cheap switch and not effect the performance or duty cycle or lessen the length of it's life in any way. Why would they not do that to get the upper hand on the harsh competition.

 

[Jim Davey]

They are more interested in keeping the basic price as low as possible. Tech Arc would fit fan as needed to a set of you specified it as an option when you placed your order.

 

[Jim Davey]

Also, if you fit a ragingly powerful fan to a machine you can specify cheaper smaller power components and still get a respectable duty cycle.

 

[Richard.]

So would duty cycle be effected then if FAN was implemented to a cheap machine?

 

[Jim Davey]

It isn't, it's why really powerful noisy fans are fitted to cheaper sets.

 

[wheresmejumper]

Its a matter of keeping costs to an absolute minimum.(most)people who buy rtech machines have never heard a quiet welder.its something that might never cross their mind
the thermal arc 202/186 is a budget welder too,costs kept down everywhere,ac freq only up to 150hz which is 15 year old technology.the older 185 was a higher level machine,and it had fan on demand

 

[Richard.]

The 185 is sanrex in it. Different league all together.

 

[Maker]

How did you work out it was the temperature sensor and not something else at fault? The fan in my welder hasn't worked since the day after I bought it.

 

[gordon stephenson]

The machine I am asking about is Butters (,made by Fimer) 215 amp synergic mig. Most times I'm only using 120 amps at a time and then not for long runs, Never had the machine come anywhere cutting out on over heat,but the fan does annoy me a little, I used to have an Esab 160 with a big transformer and it did not have a fan at all. So peaceful with the welder just emitting a low gentle hum,that one did not trip out on me either, Think i will start looking for the temps with Jim mentioned.

 

[Appyasme]

Was New Arc Gibson and Jackson from the North East

 

[Jim Davey]

I ran 6x 3.2mm rods back to back and the set cut out. The fan never came on and I know from experience it normally cuts in about halfway through the 3rd stick, I checked the fan wasn't stuck, it wasn't. I opened up the machine and I powered the fan from an external supply and it ran fine. I found the temperature switch and it was open circuit, which it should be when cold, but when I heated it with a hot air gun it didn't close. Technically this wasn't a five minute fix as it took about 15 minutes to go through the above diagnostics, then five minutes on the phone to order a switch, five minutes to fit and test when it came, then PAT test. Then call the client to tell him it was ready and do the invoice, by then it was an hour, which is shop minimum and exactly what I booked to the job.

 

[Jim Davey]

The machine I am asking about is Butters (,made by Fimer) 215 amp synergic mig. Most times I'm only using 120 amps at a time and then not for long runs, Never had the machine come anywhere cutting out on over heat,but the fan does annoy me a little, I used to have an Esab 160 with a big transformer and it did not have a fan at all. So peaceful with the welder just emitting a low gentle hum,that one did not trip out on me either, Think i will start looking for the temps with Jim mentioned.

Be careful, not all temperature switches are the same, most can't switch mains voltages, so if you have a 110 or 240v fan you will need to use the switch to power a relay to control the fan, it's simple enough but it's another cost and level of complexity to consider.

 

[gordon stephenson]

Hello Jim, thanks for the info. I'm not at home this week, the machine is dual voltage, Auto switching ,so long long since I looked at the spec plate, I only ever use it on 240v. I will take off the cover when I'm back and see what the fan plate says.

 

[Bill Edwards]

I too would think it down to cost.

My Inverter Fusion 200 (the phf model with all the gizmos) doesn't have the fan on all the time, it sits there silent until you're part way through a weld, then the fan kicks in for a few seconds. As the duty cycle is silly high and I've had no big jobs I've never had chance to get it hot, but I'm sure it would cut in for longer as needed.
But that sort of thing costs money, which is why it's not standard on all welding gear.
Penny pinching.

 

[Maker]

I too would think it down to cost.

My Inverter Fusion 200 (the phf model with all the gizmos) doesn't have the fan on all the time, it sits there silent until you're part way through a weld, then the fan kicks in for a few seconds. As the duty cycle is silly high and I've had no big jobs I've never had chance to get it hot, but I'm sure it would cut in for longer as needed.
But that sort of thing costs money, which is why it's not standard on all welding gear.
Penny pinching.

I've got an IFL 200 HF (Without the gizmos), it's actually a much older one made by Freeman but it's the same machine. I didn't know the fan was on demand, that's probably why I thought it was broken.

 

[Jim Davey]

I've got an IFL 200 HF (Without the gizmos), it's actually a much older one made by Freeman but it's the same machine. I didn't know the fan was on demand, that's probably why I thought it was broken.

If it's an IFL it probably is!

 

[Maker]

If it's an IFL it probably is!

Are they not very reliable then?