MCC or Free Standing Panel
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Upgrading?.... What are they in now?
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Keep in mind maintenance and troubleshooting.
The all in one control cabinets are definitely cheaper, but I never liked how you usually had to open the cabinet to reset/troubleshoot and you were surrounded by wiring and other equipment that was still hot for other motors, etc. I don't personally mind it too much, I just worry more about other folks, operators, etc getting in there. I'm not sure if OSHA plays a part or not.
An MCC bucket is definitely my preferance in this regard since it allows you to do reset the breaker, overloads, etc from the exterior.
The all in one control cabinets are definitely cheaper, but I never liked how you usually had to open the cabinet to reset/troubleshoot and you were surrounded by wiring and other equipment that was still hot for other motors, etc. I don't personally mind it too much, I just worry more about other folks, operators, etc getting in there. I'm not sure if OSHA plays a part or not.
An MCC bucket is definitely my preferance in this regard since it allows you to do reset the breaker, overloads, etc from the exterior.
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Think about maintenance and troubleshooting. If the drives are on a system that all has to run together, and therefore need or can be all shut down at the same time together, then the panel works. But if you need to work in or troubleshoot one drive while everything else runs, the MCC allows that to happen safely. It also allows for LO/TO of any individual motor without opening the panel door.
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They all have Powerflex 40s. The drive panels are sitting on the floor and we are thinking of upgrading and moving them into an Electrical Room
Do you mean, like literally, sitting on the floor?
Once upon a midnight dreary I worked for a company that had access to Eaton Bidmaster. We had customers that wanted Toshiba drives. So we bought Eaton MCC's with the extended bucket door because of the depth of the Toshiba drives. Then installed the Toshiba drives in our shop. Eaton could do the basic wiring far less expensive than we could. All we had to do was pick out a bucket big enough for the drive and get the control wiring and switches laid out. It was pretty slick.
I do not know if other MFG do this, I know Eaton does. The MCC plants were separate from the switch board plants.
To answer the question that may be lurking, I did work for CH then Eaton as a field service engineer (+5 years). As always equipment is manufactured to a price point.
You may have to find a salesman that is familar with MCC's and bid master. I doubt the wholesalers know about this.
Im hoping hes referring to the panels / drives being in the field near the motors they are controlling. (conveyors?)
This will change everybody's original answer as distance will have to be taken into account as well as a bunch of conduit.
You bring up a good point about the distance. I would guess the poster is familiar with the products requirements and limitations.
Your comment does bring to mind the isolation and filtering needed by drives in some applications. DV/DT filters are pretty common when applying drives. I have used a bunch of them from MTE.
With small VFD's there are a couple considerations. First one is...are all motors going to run the same speed? If so, you may want to reconsider using a bunch of small VFD's. You can use separate external disconnects/overload relays (manual motor starters) fed from the VFD and just use one or a few larger VFD's running in V/Hz mode. And this version will definitely go into a panel.
Second consideration is how far the motors are from the VFD's. If it's over 100 feet, you will need dv/dt filters. Those take up quite a bit of space.
Third consideration is lockout/tagout, whether or not you need secondary disconnect(s) and/or individual motor lockout as opposed to locking out a whole bunch.
Final consideration is short circuit protection of the VFD. Most VFD's have very low short circuit capability. Realistically if the transformer kVA is more than about 10 times the VFD kVA you need fast fuses to protect the VFD. At 1 HP, that means pretty much any transformer bigger than 10 kVA and you said you have 36 motors so this is an issue to solve.
That being said, I'd throw a couple suggestions out there. First consideration is to consider going with fused disconnects with longer lengths. Stick your VFD's in there and field mount them. This eliminates any need for filters (issue 2) and provides local disconnects (issue 3) and fusing (issue 4). This makes it a "combination VFD".
Second is with the MCC...disagree with using MCC on small drives. The only thing it does for you is prebuilt power distribution and lockout/tagout. Other than that it's a very expensive fuse panel or MDP. Working inside buckets for wiring is a pain in the rear even if you remove them compared to working on an open panel on a table before inserting into the enclosure. It is certainly not going to be cheaper than the combination VFD concept and it is going to be very hard to beat the cost of a relatively efficient panel shop.
The traditional route is definitely the panel though, if none of the 4 issues I pointed out don't push you into another direction. But the form factor of the control panel definitely leaves something to be desired when it comes to especially LOTO. If you can solve that easily (common lockout point, lock out the door on distribution rather than individual devices) and you don't need secondary disconnects then an industrial control panel is the traditional, smallest, and cheapest way to go.
Second consideration is how far the motors are from the VFD's. If it's over 100 feet, you will need dv/dt filters. Those take up quite a bit of space.
Third consideration is lockout/tagout, whether or not you need secondary disconnect(s) and/or individual motor lockout as opposed to locking out a whole bunch.
Final consideration is short circuit protection of the VFD. Most VFD's have very low short circuit capability. Realistically if the transformer kVA is more than about 10 times the VFD kVA you need fast fuses to protect the VFD. At 1 HP, that means pretty much any transformer bigger than 10 kVA and you said you have 36 motors so this is an issue to solve.
That being said, I'd throw a couple suggestions out there. First consideration is to consider going with fused disconnects with longer lengths. Stick your VFD's in there and field mount them. This eliminates any need for filters (issue 2) and provides local disconnects (issue 3) and fusing (issue 4). This makes it a "combination VFD".
Second is with the MCC...disagree with using MCC on small drives. The only thing it does for you is prebuilt power distribution and lockout/tagout. Other than that it's a very expensive fuse panel or MDP. Working inside buckets for wiring is a pain in the rear even if you remove them compared to working on an open panel on a table before inserting into the enclosure. It is certainly not going to be cheaper than the combination VFD concept and it is going to be very hard to beat the cost of a relatively efficient panel shop.
The traditional route is definitely the panel though, if none of the 4 issues I pointed out don't push you into another direction. But the form factor of the control panel definitely leaves something to be desired when it comes to especially LOTO. If you can solve that easily (common lockout point, lock out the door on distribution rather than individual devices) and you don't need secondary disconnects then an industrial control panel is the traditional, smallest, and cheapest way to go.
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Trying to figure out exactly what you are looking at here. Where are all these motors located? Are they indoors or outdoors? Would the MCC be an outdoor unit or inside? Are these going to be variable speed controlled by an input like a 0-10v or 4-20ma? If so how far away would it be from the dcs or plc? If you can pick inside in an mcc vs outside in a standalone panel I would definitely go for the mcc method. It is a lot easier to keep in clean and climate controlled. I know VFDs are pretty stout and being for only 1hp they aren’t very big but will still need a big enough enclosure to let them breath. The elements around here are crappy and we have many boxes outside that are rusted apart. It’s hard to really say without knowing where everything is ran from and what you are going to do with it. Would it be possible to get away with running a soft start on them or do you need the actual speed control?
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