Hi,
I'm having some trouble finding an exact replacement part for the following power relay:
FRA1TNA - E
DC 110V
40A 240VAC


The relay is from an iVAC Switch Box. The employee at my local electronics store mentioned that the following part can be substituted instead:
T9AS1D12-110 - Power Relay, SPST-NO, 110 VDC, 30 A

http://www.newark.com/te-connectivi...1D12-110&ddkey=http:en-US/Element14_US/search

I am a novice when it comes to electronics in general. The part has to be special ordered and the only difference I see is 30A instead of the original 40A.
My questions are:
1. What is the difference between the two and can the 30A power relay be used to replace the original 40A power relay?
2. What happens when you use a lower DC voltage instead of 110VDC?
3. Are there any safety hazards from using a lower amperage?
4. Which sites do you use to order parts in Canada besides digikey and mouser?

 

1 It depends on the ACTUAL current that it is switching. The current that is switching must be less than 30 amps. But is not good practice to run items at the maximum rating. The contact voltage rating must also be suitable fot the application.

2 If the coil is rated less than 110 volts DC it will burn out. (If it is rated higher it will not pull in.)

3 Yes if you exceed the rating. (It is very unlikely a manufacturer would use a 40 amp relay if it was not required.)

4 You will need someone from Canada to answer this question.

You also need to consider the physical construction of the relay and the pinout if it is PCB mounted.
I have just looked at your left hand picture again. It is possible the 110 V DC could be the contact rating if it is switching DC. If so you need to find out the coil rating. My assumption when answering your numbered questions was that the 110 volts DC was the coil rating. Is there any more information on the relay ? If not you will need to give details of what is doing. What it is part of, what is driving the coil and what volltage and current it is switching.

Les.

Les.

 

This should be the data sheet for your relay. Apparently going from 30 amp to 40 amp contact ratings was an upgrade. The relay my guess is what switches current to your vacuum or dust collector so the relay needs to handle whatever that load is. Have you tried contacting the manufacturer?
CONTACT US
iVAC
120 Iber Road, Unit 108
Stittsville, ON K2S 1E9
info@iVACswitch.com

Telephone: 613.599.8988
Direct: 1.800.775.5579
Technical Support: 1.800.775.5579
email: info@ivacswitch.com

My guess would be they should be able to provide you with the part.

Ron

 

1 It depends on the ACTUAL current that it is switching. The current that is switching must be less than 30 amps. But is not good practice to run items at the maximum rating. The contact voltage rating must also be suitable fot the application.

2 If the coil is rated less than 110 volts DC it will burn out. (If it is rated higher it will not pull in.)

3 Yes if you exceed the rating. (It is very unlikely a manufacturer would use a 40 amp relay if it was not required.)

4 You will need someone from Canada to answer this question.

You also need to consider the physical construction of the relay and the pinout if it is PCB mounted.
I have just looked at your left hand picture again. It is possible the 110 V DC could be the contact rating if it is switching DC. If so you need to find out the coil rating. My assumption when answering your numbered questions was that the 110 volts DC was the coil rating. Is there any more information on the relay ? If not you will need to give details of what is doing. What it is part of, what is driving the coil and what volltage and current it is switching.

Les.

Les.

The iVAC Switch Box belongs to my dad and I'm trying to repair it for him. Every time the miter saw is in used, the dust collector automatically switches on. I don't know the specific model of the miter saw but a quick google search revealed that the brand miter saw he uses is rated at 15 amps. I have no idea what the motor amp draw is for the dust collector.

It is PCB mounted and there's no other information on the relay. My dad says to just order the 30A relay but I wanted to be sure before proceeding. Will the 30A work in this case given the information I provided above?

Thanks for taking the time answering the questions, I've learned a lot.

 

This should be the data sheet for your relay. Apparently going from 30 amp to 40 amp contact ratings was an upgrade. The relay my guess is what switches current to your vacuum or dust collector so the relay needs to handle whatever that load is. Have you tried contacting the manufacturer?
CONTACT US
iVAC
120 Iber Road, Unit 108
Stittsville, ON K2S 1E9
info@iVACswitch.com

Telephone: 613.599.8988
Direct: 1.800.775.5579
Technical Support: 1.800.775.5579
email: info@ivacswitch.com

My guess would be they should be able to provide you with the part.

Ron

You are right, the iVAC Switch Box powers on the dust collector automatically when the miter saw is in use. If the dust collector is, for example, rated at 10 amps, then the 30A relay could be installed irregardless of what the miter saw amperage is?

I believe the warranty expired, but I will try to contact the manufacturer to see if they sell the relay.

Thanks for the suggestion.

 

Dust collectors are generally Universal motor blower fans, I would not expect it to be anything near 40a.
Also, if the relay itself is in a dust free atmosphere, removing the small vent pip on the corner can prolong the life of the relay.
Max.

 

We still don't know what the coil voltage rating is and if it is AC or DC. Can you measure the voltage across the relay coil when the saw is running ? If not can you trace out the circuit that drives the relay ? If the fault with the relay is not an open circuit coil then measuring the coil resistance will help to identify the coil voltage using the information in the link that Ron posted in post #3. You may also need to remove the cover from the old relay and look at the pole piece to see if it has a copper shading ring. If it did it would be an AC relay.

Les.

 

Dust collectors are generally Universal motor blower fans, I would not expect it to be anything near 40a.
Also, if the relay itself is in a dust free atmosphere, removing the small vent pip on the corner can prolong the life of the relay.
Max.

That is useful to know, but where exactly is the small vent pip? Thanks.

 

It looks like it has one in the first picture in the OP, top right.
Max.

 

We still don't know what the coil voltage rating is and if it is AC or DC. Can you measure the voltage across the relay coil when the saw is running ? If not can you trace out the circuit that drives the relay ? If the fault with the relay is not an open circuit coil then measuring the coil resistance will help to identify the coil voltage using the information in the link that Ron posted in post #3. You may also need to remove the cover from the old relay and look at the pole piece to see if it has a copper shading ring. If it did it would be an AC relay.

Les.

I have no access to my dad's saw and I don't know how to trace out the circuit. Sorry, I have limited knowledge on this matter. The cover is epoxy base but I can try to pry it open if possible. A picture of the board may be of use?

 

It looks like it has one in the first picture in the OP, top right.
Max.

Where the red arrow is pointing at? It appears to be a part of the cover as a whole. What is the best method of removing it?

 

Did you measure the resistance of the realy coil ? I am assuming you must have a DVM to have diagnosed the relay to be the cause of the problem. If you can take a picture of the FULL board .(Not a cropped version.) If we can see the both the etch side and component side we may be able to trace out the schematic. Can you also tell us the capacity and voltage rating of the two capacitors with some means of identifying which is which. (For example The one next to the white neutral wire.) Are there any markings on the transformer and if so what ?
For the benifit of the other members trying to help the 1N4740 is a 10 volt 1 watt zener diode. The TO220 device is a P3NK60ZFP (600v MOSFET.) This is a link to the data sheet.

Les.

 

Where the red arrow is pointing at? It appears to be a part of the cover as a whole. What is the best method of removing it?
View attachment 145437

That is the one, usually it snaps off or use small snips, it normally exposes a small hole..
Max.

 

I'm not familiar with that model of Dust Collector controller but, in general, they work by sensing the current draw. The saw is plugged into an outlet that has the current sensor in it and then kicks in the relay when current flows. No changes to the shop tool needed.

My experience with iVac has been that they made claims in their advertising for a product I bought. The packaging had a lesser claim and product inside was labeled with an even lesser claim. Not a huge fan of that company.

 

Did you measure the resistance of the realy coil ? I am assuming you must have a DVM to have diagnosed the relay to be the cause of the problem. If you can take a picture of the FULL board .(Not a cropped version.) If we can see the both the etch side and component side we may be able to trace out the schematic. Can you also tell us the capacity and voltage rating of the two capacitors with some means of identifying which is which. (For example The one next to the white neutral wire.) Are there any markings on the transformer and if so what ?
For the benifit of the other members trying to help the 1N4740 is a 10 volt 1 watt zener diode. The TO220 device is a P3NK60ZFP (600v MOSFET.) This is a link to the data sheet.

Les.

I've repaired a few things before and when you expose the circuit, the problem is usually visible; either a blown out fuse or burnt component(s). Other times I watch videos on youtube to try and diagnose the problem with a multimeter. My dad's friend had the exact switch box, working of course. I suspected it was the relay so I desoldered the working relay onto my dad's switch box and when I tested it by plugging in hair dryers, everything was back in working order. In this case, the problem is the bad relay itself.

I contacted the manufacturer and they mentioned the upgrade from 30A to 40A allows a higher HP vacuum to be used from 6 amps to 8 amps, respectively. They also mentioned about the start up surge current and how customers were experiencing problems prior to the upgrade to 40A. Can start up surge current hit or exceed levels at 30A or more?

That is the full board with the T1 cropped off a bit. The reason for the cropped image is due to posting guidelines: "Please keep the attachment size under 300K if possible." by bertus, administrator. The capacitors are 10uF 250V. There are no markings on transformer. I can upload the back side if you still need it, let me know.

 

This should be the data sheet for your relay. Apparently going from 30 amp to 40 amp contact ratings was an upgrade. The relay my guess is what switches current to your vacuum or dust collector so the relay needs to handle whatever that load is. Have you tried contacting the manufacturer?
CONTACT US
iVAC
120 Iber Road, Unit 108
Stittsville, ON K2S 1E9
info@iVACswitch.com

Telephone: 613.599.8988
Direct: 1.800.775.5579
Technical Support: 1.800.775.5579
email: info@ivacswitch.com

My guess would be they should be able to provide you with the part.

Ron

I took your suggestion and contacted the manufacturer. They were willing to send one if I cover the shipping cost, however they are out of stock at the moment and do not know when exactly they will be in, may take a few weeks. Thanks for the suggestion.

 

That is the one, usually it snaps off or use small snips, it normally exposes a small hole..
Max.

I contacted the manufacturer and they mentioned the upgrade from 30A to 40A allows a higher HP vacuum to be used from 6 amps to 8 amps, respectively. They also mentioned about the start up surge current and how customers were experiencing problems prior to the upgrade to 40A. Can start up surge current hit or exceed levels at 30A or more and last for several seconds?

 

I'm not familiar with that model of Dust Collector controller but, in general, they work by sensing the current draw. The saw is plugged into an outlet that has the current sensor in it and then kicks in the relay when current flows. No changes to the shop tool needed.

My experience with iVac has been that they made claims in their advertising for a product I bought. The packaging had a lesser claim and product inside was labeled with an even lesser claim. Not a huge fan of that company.

If you don't mind me asking, which dust collector controller do you use currently/recommend?

 

There are several ways round the picture size problem.
1 Take the picture with the camera a little further away from the board. Taking the picture from a greater distance would also avoid viewing the parts at the edge of the board at such a steep angle. You can then crop the image with software.
2 Change the resolution setting on your camera to a lower resolution.
I have just looked at the image information for the picture of the board and it is only about 87 K bytes so you don't have a problem
That is a very risky fault finding method fitting a suspect part in a good board. There are many situations where the faulty part could have destroyed components on the good board. We still need the information requested if we have any hope of working out what the relay coil rating is.
One other question. As you do not say what country you are in we don't know what your mains voltage is likely to be so what is you mains voltage ?

Les

 

Can start up surge current hit or exceed levels at 30A or more and last for several seconds?

Typically the Inrush Current, Input Surge Current or also called the Switch On Surge Current can be as much as ten to twenty times the normal motor run current. This high current normally only last for about the first 1/2 cycle of the input current or on a 60 Hz system about 8.3 m/seconds. The subsequent peaks and valleys of the incoming waveform will drop off quickly. Fuses and circuit breakers take this into consideration when chosen for motor start circuits. So really only the first few cycles of the current only last well below one second. I base the line frequency on you being in Canada?

You are absolutely sure the relay is faulty? If you have a good ohmmeter you may want to isolate the relay and measure the coil resistance. Coil resistances are listed in the relay data sheet. Since these controller units allow the vacuum to run a short time after power is removed from the load I am guessing there are some other electronics involved.

Ron