Right..., but if I used gearbox, do you think they can still be damaged ?

As per #18, they can be stalled with no ill effect IF ran at rated current.
Also the MCCB usually will trip on reset if fault still exists.

 

I would program the PLC to allow say one reset after trip incidence, then alarm if re-trips instantly.

This I would strongly consider. When a breaker trips it normally trips for good reason. You do not want to just continuously reset less knowing the cause.

Ron

 

Right..., but if I used gearbox, do you think they can still be damaged ?

No and I only suggested a gearbox because I have seen a gearbox used for disconnect and connect purposes. While I have no idea and looking at these breakers I see no mention of how much rotation in degrees is needed to reset them. I have also worked with breakers which need rotated in one direction before being rotated in the opposite direction for reset. Sometimes I know why a breaker has tripped and just reset it. However, other times not so fortunate. Breaker trips and I reset right into another trip so obviously I need to find the fault which caused the trip. Over all the years I have seen some strange reasons for breaker tripping. This includes industrial and residential.

All that aside before I would settle on a motor to reset a breaker in this case I want to know the required rotary force and if more than one direction of travel is necessary as well as how much travel. Once all of those factors are known then I would start motor considerations. You may also want to figure cost options. All of this is pure speculation on my part.

Ron

 

According to the parts quoted, it takes 90° turn, either way.

 

I am really quite tired of the acronyms MCB and MCCB! I think that once before Msoft used MCB to mean miniature circuit breaker, which is a silly nomenclature, really MCB in a JIC drawaing is Main Circuit Breaker. And it only appears at the top by the first breaker in a system. The rest of the breakers are BRANCH circuit breakers no matter if they are miniature or not.

Problem is manufacturer isn't provide remote control option... it's entry-level series and mid-level series...

My advice in post #9 was to seek information. In no way at all was I suggesting to purchase remote resettable breakers. Some organizations will offer advice about their products, while others will only try to UPSELL to a more costly product while refusing to provide needed information. If the manufacturer is unable or unwilling to provide the information about the recommended speed and torque to be used for operating their products then I recommend selecting a different brand of products.

Now there is also a real concern about who is liable if something fails and damage or injuries result. Consider that in most applications circuit breakers are a safety device, and if a modified safety device fails, no matter what, will presume that whoever did the modification was just as ignorant as the jurors are. At least that is how it tends to work in the USA.
So consider that you have no control over who adjusts or modifies the controls program in that PLC controlling the resets. There is one more possible source of things going wrong.

 

According to the parts quoted, it takes 90° turn, either way.

Right... from open to close position it takes 90° turn, and 45° turn from trip to open position...
*Note, after breaker tripper it needs to be in open position first before to close position again...

 

I am really quite tired of the acronyms MCB and MCCB! I think that once before Msoft used MCB to mean miniature circuit breaker, which is a silly nomenclature, really MCB in a JIC drawaing is Main Circuit Breaker. And it only appears at the top by the first breaker in a system. The rest of the breakers are BRANCH circuit breakers no matter if they are miniature or not.

I say MCB is for miniature circuit breaker... and MCCB for molded case circuit breaker...

 

My advice in post #9 was to seek information. In no way at all was I suggesting to purchase remote resettable breakers. Some organizations will offer advice about their products, while others will only try to UPSELL to a more costly product while refusing to provide needed information. If the manufacturer is unable or unwilling to provide the information about the recommended speed and torque to be used for operating their products then I recommend selecting a different brand of products.

Yes... I think it's all about monetization... only NSX series is available with motorized versions... It's about 500% price equivalent of EZC series in CN... even with mid-range series only few MCCB have official motorized accessories... and Schneider official still don't give me answer for this problems (I ask for how many torque I needs, and relevant problems that if may have from MCCB modification)...

 

Now there is also a real concern about who is liable if something fails and damage or injuries result. Consider that in most applications circuit breakers are a safety device, and if a modified safety device fails, no matter what, will presume that whoever did the modification was just as ignorant as the jurors are. At least that is how it tends to work in the USA.
So consider that you have no control over who adjusts or modifies the controls program in that PLC controlling the resets. There is one more possible source of things going wrong.

It's difference from country to country... I just needs another company for inspection, and they have liability and responsibility for my finished task... usually they tested in their own lab for safety reasons... and I think that's safe way... if my works is disapproved then I needs to fix it... no really needs to worry about safety...

 

Do you think NEMA 23 stepper motor with 4nm torque with gearbox will be enough for this task ? @MaxHeadRoom @Reloadron

 

Can I damaged MCCB if I used over-torque motor ?

 

Can I damaged MCCB if I used over-torque motor ?

No, not likely. Just don't overtravel it or something will break. That assumes enough force is available to overtravel it.

Ron

 

Do you think NEMA 23 stepper motor with 4nm torque with gearbox will be enough for this task ?

Did you take any measured data to confirm?
What is the ratio of the GB?
The torque increases in direct proportion to the reduction.

 

I say MCB is for miniature circuit breaker... and MCCB for molded case circuit breaker...

Thank you for the clarification. I never those two characteristics of circuit breakers when describing a system. They are main and branch, sometimes described by the voltage in their circuit or the device they are protecting. Now you may see why I get confused in these threads some times.

 

Thank you for the clarification. I never those two characteristics of circuit breakers when describing a system. They are main and branch, sometimes described by the voltage in their circuit or the device they are protecting. Now you may see why I get confused in these threads some times.

Yes... in this case MCCB is for main breaker and branch breaker too... and I use it for DC breaker too... Schneider EZC series supports DC voltage... and I use 96v DC with three wire system (400a maximum capacity)...

 

Did you take any measured data to confirm?
What is the ratio of the GB?
The torque increases in direct proportion to the reduction.

Its 80:1 gearbox ratio, available in 3nm and 4nm

 

 

View attachment 276205

@MaxHeadRoom @Reloadron

 

I assume since this remote reset is desired, there is implied a long distance from the operator to the breaker. A scenario like on a ship or inside a large a plant, where the operator might be separated from the breaker (and from the controlled equipment) by tens of meters and many walls.

In almost every case, when a circuit breaker trips, there is a reason. And consider that while there are quite a few remote-trip options offered I am not aware of a remote reset option being offered. So there are undoubtedly good reasons beyond what I can see.

+1


Think about the sequence of human actions normally required to reset a breaker.

1. Investigate involved equipment, check for jams, etc.
2. Walk circuit back to MCC or control panel.
3. (For this kind of breaker) open control panel, locate breaker.
4. Is it actually tripped or has it been turned off? Is it tagged out? Why?
5. Reset/Turn breaker breaker on. Does it immediately trip?

Now consider whether the above sequence is required due to an unavailability of the technology needed to remotely reset a breaker, or whether it is deliberate.

Steps 1: this allows you to see the cause of the problem more often than not. Is there a smoking motor? What if there is a jam and the jam is a person?

Step 2: this allows you to see if there is a problem in the circuit that the breaker is meant to protect. Has a forklift crushed a conduit against a wall? Is there a hapless idiot with a non-insulated multi-tool holding a severed cable and trying to "splice" it?

Step 3: this allows you to see the other end of the system where the problem might be. Is there a smell of magic smoke inside the cabinet? Where is is it coming from?

Step 4: how do you lock out/tag out something like this? With a bit in the PLC? Sorry but I am not willing to work on something that can be flipped on at whim by the operator after shift change.

Step 5: when you turn the breaker on, any unsettling noises? Smells? Explosions? Screams of anguish?

All or most of these steps are assuredly going to be skipped altogether if there were a remote reset. The person blindly flipping the breaker from a touchscreen in cozy control room somewhere is going to have no idea of the consequence of their actions. They are potentially starting fires, destroying motors, killing people, etc. every time they press that button and they probably won't be sufficiently warned of the dangers.

The process of resetting a breaker is meant to demand a fairly intimate involvement from a human. Putting this kind of device on it is negating nearly its entire purpose.

 

Regarding the operation of the breakers, I wonder if there is any "over-center" toggle type of snap action, where, when moved past some point in the rotation the tendency is for the motion to continue without additional force applied. Most of the lever actuated switches that I am familiar with operate this way, as well as most of the rotary switches. Likewise all of the smaller toggle-style circuit breakers. (By smaller, I mean less than 50 amps and less than 300 volts rated)
Almost all switching devices made for power switching, not signal switching.
The reason that I ask is that a very simple scheme to assure proper operation is to have enough free-play in the external operating mechanism so that once the device has been moved past that over-center point it may move to the intended position on it's own, rather than being restrained by the operating mechanism. I am aware that system free-play is against all CNC rules, but remote operation of a circuit breaker or switch is an entirely different world.
And it would certainly solve many of the anticipated concerns about ever-travel and damage.