Hydrovane HV02 three phase to single phase conversion - motor swap and control box rewire

[weatherman]

Hi everyone, I recently have been given a hydrovane hv02 three phase compressor but have been looking to convert it for single phase for use in my home workshop. Before I go ahead and sink money into the wrong parts I thought it would be best to see if anyone here has any experience with a motor swap and rewiring of the controller/starter from 3 phase to single.

I have opened up the control box and there is a single phase transformer that has 240 and 400v inputs so swapping the input for 240v and rewiring the two contactors for single phase should take care of the motor start side of things right? I found a user manual online with the instructions for single phase input but no info on the motor connections. None of the circuit diagrams for the single phase hv02 are publicly available so I'm a little stumped but hopefully will work it out.

Here is one of the motors I have found that I think will fit correctly. Unfortunately I have not found a compatible 2.2kw single phase web motor with the flange mount needed but I think this would work. AMTECS motor 2.2kw - The motor that I think required is a 2.2kw 2 pole 2.2kw 90 frame motor.

If anyone here has had any experience with performing this conversion your pointers will be much appreciated. There are a few threads knocking around with people talking about performing the conversion so I know it is definitely possible.

Thanks

 

[Pete.]

Why can you not fit a VFD and keep the original motor?

Pardon our interruption...

 

[weatherman]

Why can you not fit a VFD and keep the original motor?

Pardon our interruption...

I wanted to keep the machine as portable as possible. The plan is to be able to move the compressor to another workshop when needed. I had considered this option but don't really like the idea of having a wall mounted VFD with the wiring running from the compressor to the VFD and back. I can't see there being enough space to mount the VFD directly to the machine either.

 

[Seadog]

Buy an inverter.

 

[mike os]

Mount the vfd on the compressor

 

[Barking Mat]

Really bad idea.

Sell it to me cheap, I'll be doing you a favour.

That models really bad, the colour will clash with your workshops, etc......

 

[weatherman]

Why can you not fit a VFD and keep the original motor?

Pardon our interruption...

Would I still be able to use the original control box or would I have to do away with that and replace it with the VFD? I'm guessing the vfd would take the output from the danfoss pressure sensor and the motor thermistor to stop the motor when it reaches pressure or overheats? Don't really have much experience using VFDs but am reasonably comfortable with electronics and the safety side of things.

 

[Seadog]

The VFD is wired directly to the motor. The switch in the pressure switch is used to control the VFD.

 

[6ply]

It already has a switch box mounted the side, doesn't it? Remove that box and replace with one slightly larger. VFDs are mostly quite compact and should be fitted inside a box anyway (wall mounted or not).

 

[Jelly_Sheffield]

The VFD is wired directly to the motor. The switch in the pressure switch is used to control the VFD.

It's possible to both use the pressure switch as per the existing setup, or wire it to the pressure & temp sensor and program it to ramp up/down the power at various pressure and temperature readings...

Depends how clever you want to get with it, and how much functionality the VFD you chose has... Some are very basic, whilst other have near PLC levels of customisability and multiple I/O channels.

 

[Seadog]

It's possible to both use the pressure switch as per the existing setup,

How?

 

[awemawson]

I replaced my HV02 motor with one from ebay a year or two back from this seller:

etd-trading (5799)

This thread may be informative as well

Mending a Hydrovane HV02 Compressor Fan / Motor Drive

Mending a Hydrovane HV02 Compressor Fan / Motor Drive

www.madmodder.net

 

[daleyd]

How?

I don't understand that either - a pressure switch is typically giving a digital signal at a set pressure - eg once the pressure goes above X Bar/PSI etc the switch is ON.

If you want to control off different pressure values then you would need a transducer, and an appropriate analogue input to read the signal/take the required action...

 

[awemawson]

The hydrovane pressure switches on my three hydrovanes are all nomally closed mechanical switches opening on rising pressure and have two adjustments - operating pressure and hysteresis width - both working off the pressure sensing bellows using springs.

 

[Seadog]

Exactly, Andrew. You use one set of contacts to switch the compressor on and off.

 

[weatherman]

I replaced my HV02 motor with one from ebay a year or two back from this seller:

etd-trading (5799)

This thread may be informative as well

Mending a Hydrovane HV02 Compressor Fan / Motor Drive

Mending a Hydrovane HV02 Compressor Fan / Motor Drive

www.madmodder.net

Thanks for the pointers with the eBay link and the thread. Pretty sure I need a b35 mount 90 frame motor, can you remember the mounting size for the motor you purchased?I have obtained the wiring diagram for the hydrovane hv02 so hopefully it won't be too complex to rewire if I decide to go down that route.

 

[awemawson]

These are the details from my ordr confirmation email on 10/02/2020

SKU: MOTOR POWER KW: 2.2KW 3 HP, MOTOR SPEED RPM: 2800RPM, MOUNTING VARIATIONS: FOOT AND FLANGED B35
Total: £168.99
Order number: 22-04517-76618
Item ID: 202349212257

 

[Jelly_Sheffield]

How?

It will depend on the VFD, but generally to use the pressure switch as currently installed, you'd connect:

- it's common contact to the auxiliary common terminal on the VFD.

Then connect either

- it's Low Level contact to the auxiliary on terminal on the VFD.
- it's High Level terminal to the auxiliary off terminal on the VFD.
- and configure the VFD to use the aux on-off terminals in latching mode

or

- connect the contact (if single) to the aux on or off terminal (depending if it's NC or NO configuration)
- and configure the VFD to use the relevant aux terminal in momentary mode.

In no case should the output of a VFD be switched, only bad things will happen.


As to the other half of my response... If the compressor has only got a purely mechanical or integrated switch, then you can't control it based on multiple setpoints (unless the switch itself has multiple contacts and a way to set them).

The Hydrovane installations I've worked with all had pressure control via 4-20ma transducers connected to a seperate controller which handled switching and digital output to the HMI/DCS (or had the 4-20ma signal going directly to the analogue input of a PLC for independent automatic operation), with a mechanical High-High-Level switch on the accumulator(s) linked to an independent safety relay circuit.

I assumed the smaller models would be similarly configured in which case, (with a suitability advanced VFD capable of taking analogue I/O) you'd just wire the transducer directly to the appropriate VFD terminals and program accordingly.

Obviously assuming that the kind of Hydrovanes used to provide process air to a whole plant are representative of how the built their whole range as a manufacturer was an oversight.

 

[Seadog]

It will depend on the VFD, but generally to use the pressure switch as currently installed, you'd connect:

- it's common contact to the auxiliary common terminal on the VFD.

Then connect either

- it's Low Level contact to the auxiliary on terminal on the VFD.
- it's High Level terminal to the auxiliary off terminal on the VFD.
- and configure the VFD to use the aux on-off terminals in latching mode

I'm well aware of how to do it, but it seemed that you were suggesting different set points and utilising those.

 

[Jelly_Sheffield]

I'm well aware of how to do it, but it seemed that you were suggesting different set points and utilising those.

That's the literal opposite of the question you asked though!

In any case, have you read the second half of my response?

Where I addressed the question I suspected you wanted to ask, and explained exactly why I thought that would be possible by disconnecting the switching element entirely, and directly reading the pressure transducer (as long as the VFD had that functionality)?

Obviously that isn't possible if it's not a model of compressor which uses an independent pressure transducer.

(although they're available for under £20, so it's not like there's a huge barrier to adding one if progressive control was a thing that was desirable).