Monarch 10EE and VFD conversion

The soft starts require incoming 3 phase and the switch controls the soft start (soft start itself is the switch for the motor).

My whole house only has 100 amps... The 10EE is no longer being considered. I found a very very nice Siamp lathe just up the road. It's got a 5hp motor, so I should have no problems with that. And, it's 50Hz, so no issues with it down under. It's just a bit more than I can afford at the moment. :( But... I have seen soft start controls for 3 phase motors. If I run into issues with any motor with an inrush draw that blows fuses or pops breakers, these might be a good option?

Question is, do they install between the motor and mains, and work automatically upon current flow? Or are they used as a switch between mains and motor? The former is essentially a zero hassle install. The latter, seems it would require a rewire of the starting switch on say, a lathe?

Jon

Download and read the manual for a VFD drive. Not all require a three phase input, either. Some have to be derated for single phase service.

Would you have an example of a single phase "soft start"?

Hate to showcase my denseness when it comes to stuff like this, but I'm not clear on your description. Does the soft start require an input (remote contact closure) to work, or is it a passive inline device that does it's thing automatically upon current flow?

Thank you,

Jon

It can. Considering your programmer background, two big remote-control power supplies with ethernet interfaces driven by a PC. Make that two very big power supplies. These are commercially available.

The control law is not simple (I bet those two pots on a shaft are full custom), but would be easy to program. The hard part will be figuring out the exact control law, unless Morarch put enough details in a patent.

Hmm. Did a little searching using Google Patents (because USPTO search does not go back far enough).

Monarch does give a lot of detail in their patents. Here are some hits; there may be more:

I haven't read these, but they are clearly on point.

To get printable copies, enter the patent numbers at . (You can also use Google Patent, but be aware that Google sometimes mangles the drawings.)

Joe Gwinn

I'm talking about the input to the VFD. WTF would you have to derate a VFD drive with a single phase load?

A soft start is NOT a VFD. It works completely differently.

To soft start a phase converter, the standard way is to use a pony motor start.

To run three phase machinery from single phase, to get soft start, the easiest is to get a VFD (which is not a soft start, but has a benefit of a soft start in addition to other benefits).

I was asking about a soft start device, which is NOT a VFD, it's used to reduce inrush current and mechanical shock to whatever the motor is driving. Not sure exactly where they're used, nor how. I've just seen them on ebay now and then, so aware they exist.

This question is totally removed from the discussion of getting that Monarch up and running. Rather, I'm looking at other lathes, some of which have 10hp spindles. All I would be looking to do is reduce the startup current.

Yeah, could go see if I can hunt down a manual, just thought I'd ask here, on the chance someone has used them and knows how they operate.

Jon

Looking into using a soft start with 3 phase input to a 3 phase motor,

-just- to reduce starting inrush IF I decide I really want a lathe with a 10hp motor. If it'll do what I want, it makes a 10hp lathe doable, otherwise I'll have to stay at 5hp or less.

Any discussion of a VFD has nothing to do with the situation I'm looking at. Maybe I'll just see if I can hunt down a manual online.

Thanks,

Jon

Oi! Should have just done the research, took me all of 4 minutes to find that not only do they require external switching to engage, but at least the ones at Automation Direct require 24v power. And, for what they cost, at least in the lower HP ratings, I might as well go with a VFD for the additional benefits provided....

Jon

Soft start is a function, not a device.

Soft start is a function of the VFD. Otherwise it would blow the semiconductors the first time it applied power to the motor.

I suggested the manual, because you'll have more questions, and the manual describes how the entire system works so it's easier to grasp the basics. :)

D C motor drives are available to drive both PM and field wound motors. They are designed with current sensing to shut down for field loss condition. The Allen Bradley 1336 series is one such drive. Fincor is another. I would not screw with the DC motor unless it needed new brushes or some other minor maintenance. Unless you are operating the machine 24/7 the brushes will last a very long time. It is a very minor project to install a D C drive. The hardest thing is to add a tach generator for better speed control if the motor doesn't already have one.

John

Correction the AB DC drive is a 1395 series

John

Hey Iggy,

As I wrote previously, the peril with using two separate sources is in losing the source for the field winding . If the current supplied for the armature is available, the motor will literally overspeed to destruction. Kirchoff's Law will apply. Immediately!!!!

SNIP

SNIP

Hey Jon,

Soft-Start is very common on hydraulic elevators, especially if the elevator is of any size. It helps extend the motor life, and reduces pulley wear and belt wear of the multi -Vbelts (some are direct drive pumps and don't have the V-belts). But for the owner/customer, it REALLY cuts down on "dimming the lights" in the building. The only instant load on the motor at start-up is the motor itself and the screws in the pump, which is unloaded for at least a few seconds.

There is some use of SoftStart on large MG sets, but in general the MG sets are going the way of the Dodo-bird and being replaced on new installations with V.V.V.F. (Variable Voltage-Variable Frequency ) control and use new style AC motors designed for the duty. "Standard" AC motors are not able to handle VVVF, due to tremendous harmonic problems. I don't know if the same sort of problems are the reason that some common use AC motors today are noted as being designed for VVF use. I really suspect that has more to do with heating than harmonics.

Take care.

Brian Lawson, Bothwell, Ontario.

Not to hijack the thread, but does anyone have or know where I can get a service / repair manual or schematic for the ABB ACS-301-4P9-3 VFD? I have it up and working (spins the drive, speed control and fwd/rev work) but DHL managed to drop it (from quite a height) in transit and there's no DC to the control/programming panel so I can't get in and set the various motor and braking parameters... The control board (not the programming panel, the top board in the main unit) is all surface-mount and multi-layer, and is going to be a sod to trace, although no so hard to add a few repair jumper-wires if I can find what's broken and where.

I've tried ABB's UK distributors, their answer was "we don't keep spares/manuals/schematics for anything that old so buy a new one"!

I'd rather not, as it's oldish and so has been easily hacked to fool it into thinking it has 415V in and thus it can run the Difficult Motor in my Holbrook (England's Monarch?) C13 (415v only, 3-phase, 3 sets of windings for the 3 speeds) and, of course, I'm cheap ;)

Thanks all, Dave H.