3G3JV Inveter

[nguyenthanhcanh 3]

Hi! As you know, we can use single phase voltage 220VAC for Omron inveter type 3 phase 200VAC. I ever use this way for many inveters. But now I want to know clearly about advantages and disadvantages when use 2 ways: 3 phase 200V/1 phase 220V to inverter 3 phase 200VAC class: 1. Output load? 2. Input load? 3. Work life? I'm looking for your help. Thank you.

[Sleepy Wombat 27]

The later will have a larger input loading on a single phase supply.

[nguyenthanhcanh 3]

So, will the inveter break out if output load is full 100% or more, especially at starting time?

[Sleepy Wombat 27]

No, i am implying that the input cables and protective devices to the invertor need to rated at the higher current rating then say a three phase system would be.

[nguyenthanhcanh 3]

I mean that the input circuit in single phase will only withstand 2/3 current rating less than in 3 phase system. So if I have 3G3JV-A2015, I will only use for motor with power at 2/3 (1.5kW)=1kW in single phase system, instead of 1.5kW in three phase system? This is important because my customer's afraid that the inverter will be damaged early.

[PdL 71]

Theoretically you are correct of course, but why can't you use the 3G3JV-AB## series which are designed for single phase in / 3 phase out purpose ? Or am I missing something. I think Omron will not guarantee this type of use.

[OIDMBTRTECH 0]

Typically you derate a 3 phase drive 50% when used with single phase inputs. The ripple on the bus is larger with single phase and you could have nuisance under voltage trips if you try to run at higher than about 50% loads. The drive output components will not be stressed running at 50%. A 5 hp drive then becomes a 2-1/2 hp drive. The limiting factor is the input diodes capability to deliver the currnet. Some drives have larger diode rectifiers for single phase input at the rated HP. Typically these are not that large in HP either. There are phase shift filters available to allow single phase power to be applied as a 3 phase input to the drives for 100% rating usage in a situation where only single phase power available

[Sleepy Wombat 27]

Firstly, as i recall with smaller rated motors, if I had a three phase motor with a rating of 1.5 kw (2HP) and the supply 415VAC 3 phase then i connect it in STAR (WYE). If i want to connect this to a single phase supply via a Variable Speed Drive ie 240VAC input and the VSD outputs 3phase 240VAC then i connect the motor in DELTA. Typically your current comsuption goes up on the incoming of the supply to the VSD and the output current required by the drive would increase also. There is NO derating of 50%. Check the nameplate of the motor, this will indicate the operating of the motor. BTW i am implying using a dedicated 1phase in 3phase out VSD. (Not a three phase VSD and reducing the input voltage)

[nguyenthanhcanh 3]

Thanks for your zealous help.

[OIDMBTRTECH 0]

Sorry, the motor is not derated, the drive is what must be derated. If you have a 2 hp 3 phase motor and ONLY single phase power to a 3 phase drive, you need 2x the motor for drive sizing. In this example, a 5 hp drive would be necessary as there are no 4hp drives I am presently aware of being available.