VFD help required

[garrygunParticipant @garrygun]

Hi Guys,

im running a harrison m300 on a rotary phase converter runs perfectly ok, but

its pushing my electric bill extotionately high, so i thought about a digital converter

to reduce the bills, would this be possible? motor is 415v 2.2kw star i would like to be able to use all std controls eg stop start and brake control also E stop.

dont use suds pump, light is on seperate 12v supply..

any help appreciated , thanks Garry.

[garrygunParticipant @garrygun]

is it possible to run m300 on digital vfd

[Robert Atkinson 2Participant @robertatkinson2]

Hi,

Yes, this is possible and a good option. Ideally you would have to re-wire the motor to Delta. I'd suggst an Eaton DE11

https://inverterdrive.com/group/AC-Inverter-Drives-230V/Eaton-DE11-127D0FN-N20N/

Needs putting in a box with external start/stop and speed controls.

Robert G8RPI.

[garrygunParticipant @garrygun]

Thanks for quick reply,

if i rewire to delta that would make it 240 three phase, will i still be able to use harrison forward and reverse control?

[Tony RayParticipant @tonyray65007]

To get the best out of the VFD conversation you should rewire the controls to make use of its control circuitry. I did this on my M250. There was an article in MEW on an M300 conversion a few years ago. Can recommend Schneider Altivar VFDs.

[Robert Atkinson 2Participant @robertatkinson2]

Hi,

The motor is connected directly to the VFD and direction switched by a control input on the VFD. You should be able to re-wire the Harrison switch to provide the low voltage signal to the VFD if you want to. I'd have to look up the harrison wiring to give any more information.

Robeert G8RPI.

[EmgeeParticipant @emgee]

Posted by garrygun on 14/05/2021 21:14:24:

Hi Guys,

to reduce the bills, would this be possible? motor is 415v 2.2kw star i would like to be able to use all std controls eg stop start and brake control also E stop.

any help appreciated , thanks Garry.

The VFD in the link provided is not suitable for your motor, you need to at least match the kW rating of the motor.

Emgee

[garrygunParticipant @garrygun]

ok thanks guys, didnt think it was that straight forward, now i know it can be done ill check the wiring so i can use the existing switches unless someone says it not possible.

[Robert Atkinson 2Participant @robertatkinson2]

Wrong quote

 

 

Edited By Robert Atkinson 2 on 15/05/2021 09:35:48

[Robert Atkinson 2Participant @robertatkinson2]

Posted by Emgee on 14/05/2021 23:35:44:

Posted by garrygun on 14/05/2021 21:14:24:

Hi Guys,

to reduce the bills, would this be possible? motor is 415v 2.2kw star i would like to be able to use all std controls eg stop start and brake control also E stop.

any help appreciated , thanks Garry.

The VFD in the link provided is not suitable for your motor, you need to at least match the kW rating of the motor.

Emgee

Well spotted I somehow went to the wrong rating. This one will work.

https://inverterdrive.com/group/AC-Inverter-Drives-230V/Eaton-DE1-129D6FN-N20N/

The 1.5kW one would have worked OK but would have limited the power and torque to that of 1.5kW motor, OK for most work but not ideal.

Robert G8RPI.

[EmgeeParticipant @emgee]

If you join the iO Group for Harrison Lathes there is a schematic in the Files section showing how to connect a VFD to your lathe using the existing apron controls.

**LINK**

Emgee

Note from File:

Convert a 3phase M300 to single phase while retaining all the standard controls. This version works with most VFDs, including the HuanYang.

 

Edited By Emgee on 15/05/2021 10:09:30

[SillyOldDufferModerator @sillyoldduffer]

Posted by garrygun on 14/05/2021 21:55:02:

Thanks for quick reply,

if i rewire to delta that would make it 240 three phase, will i still be able to use harrison forward and reverse control?

I wouldn't!

The golden rule of VFDs is 'Do not switch the outputs!'. Doing so might generate a few thousand volts that write-off the electronics and the motor by puncturing the insulation. The existing Harrison switch probably swaps outputs, which is bad.

Instead, use the VFD's controls to control speed and direction; this is completely safe. The lathe's switch gear could be rewired to control the VFD, but it's generally easier to wire up the VFD to its own controls and leave the lathe alone. Much depends on how often the lathe's controls are used – not worth messing with the lathe's reverse switch if reverse is rarely used. It would be worth the effort if the lathe does a constant forward/reverse workflow.

Rotary converters are a good match to machines with complicated 3-phase electrics because they are bone-head insensitive! Unfortunately being dimwitted they are also inefficient. VFD's are much smarter, cheaper and efficient but also sensitive. They REALLY don't like driving more than one motor (lathes with coolant pumps etc), or having their outputs switched.

Older 3-phase machines were designed to plug into a permanent 3-phase supply, which doesn't care much when phases are switched, extra motors switched on and off, or the motor is a dual-speed type. Many of these machines are easy to VFD, others need more thought and work, perhaps replacing a coolant pump, cooling fans and the lighting with single-phase equivalents, rethinking the safety interlocks, going star to delta, and fixing a dual speed problem.

Be good to find someone who has already done a Harrison – they would know exactly how difficult the job is.

Whether machine is worth converting is a balance of the work involved against the energy saving plus other VFD advantages like speed control. My feeling is this is usually when something needs to be replaced, but I haven't seen Garry's electricity bill !!! I wouldn't be happy having a 2HP converter spinning all day every day.

Dave

[Robert Atkinson 2Participant @robertatkinson2]

I had look at this M300 manual and circuit http://vintagemachinery.org/pubs/detail.aspx?id=13849
It does not look too dificult to rewire. The controls (not shown on my snip below) run on 110V from transformer 0m1 and energises either contactor 1c1 (fwd) or 1c2 (rev).

The modification would be:

Cconnect single phase 240V to R and T.

Move primary tap on transformer 0m1 to 240V

Disconnect all wires from power contacts of 1c1 and 1c2, connect phases R & T from isolator 1a to VFD input and wires to motor to VFD output.

One power contact each from 1c1 and 1c2 in parallel to the run input of VFD, one contact from 1c2 to the reverse input of VFD. (common for these is of courses the low DC control voltage of the VFC.

Wired like that the lathe will operate as before. Of course to get full VFC benefits you would add a speed control and probably jog.

There is one issue, which is the E-Stop does not operate directly on the power input or E-stop input to the VFD. This can be fixed by connecting the VFD E-stop input to the unused 33/34 contact on control relay 0d1

Robert G8RPI.

[SteviegtrParticipant @steviegtr]

Garry has the motor rating plate got 415/240 . Some of the old 3 phase motors were 415v only windings.

Steve.

[KWILParticipant @kwil]

Garry,

As Tony says there is an article in MEW (2009), it details how I converted my M300 to full inverter supply and using all the lathe apron controls line by line details.

PM me and I can send written article to you (less photos) by email.

Edited By KWIL on 15/05/2021 11:19:55

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