how to wire a 6-lead, 480vac wye motor?

[emiller233]

we got a very expensive custom Siemens motor that we wanted to verify wiring on before we tried to start it. the nameplate just says 460 Y (see picture of nameplate).
just wanted to make sure we should wire it as Y, not a start-delta setup?

the motor has been derated for 50Hz, so the top nameplate is the standard nameplate, and the bottom one is the new derated nameplate that we should be following
its a 6-lead motor
SIMOTICS SD MOTOR TYPE:
1CV3280B Low-voltage motor, IEC Squirrel-cage rotor, self-ventilated, IP55
60 Hz, P60: IE2 4-pole * Size 280S, * 75kW (50 Hz) 86kW (60 Hz)
3 AC 50Hz 240VD/415VY * 3 AC 60 Hz 480 VY
3 PTC thermistors for disconnection (2 terminals)

 

[kwired]

Last image posted (circuit diagram) shows how to connect it, do you not understand what it is showing you?

The delta connection is the one with the triangle to the left of it, Y connection has "Y" to the left of it.

You use Y configuration for 415-480 volts and delta for 240 volts.

There are jumper bars pictured inside your connection box, use them to link whichever terminals together per whichever voltage is being supplied. Incoming leads go to the bottom three terminals shown in the diagram for either voltage.

 

[emiller233]

Last image posted (circuit diagram) shows how to connect it, do you not understand what it is showing you?

The delta connection is the one with the triangle to the left of it, Y connection has "Y" to the left of it.

You use Y configuration for 415-480 volts and delta for 240 volts.

There are jumper bars pictured inside your connection box, use them to link whichever terminals together per whichever voltage is being supplied. Incoming leads go to the bottom three terminals shown in the diagram for either voltage.

i do. others are saying it should be a star-delta setup, not just wired as Wye.

it will be on a soft starter eventually (hasn't arrived yet), but for now its just going thru a contactor.

 

[emiller233]

and it gets better...
i was just told they had originally wired it as Delta and tried to start it yesterday.
instantly blew a 400A main breaker in the building.
double checked their wiring and started it again, ran for 3 minutes and blew a fuse (class J) at the local disconnect.
then they tried to wire it to Wye configuration and it just hums and wont start now. and they cant find a megger to test it...

 

[kwired]

i do. others are saying it should be a star-delta setup, not just wired as Wye.

it will be on a soft starter eventually (hasn't arrived yet), but for now its just going thru a contactor.

It is typical of IEC motors, you connect them wye for the higher voltage and delta for the lower voltage.

Star-delta is a starting method for when you want to reduce the instantaneous current upon energizing, would generally only be used on maybe 50 or more HP motors and needs more than just a three pole contactor for a controller.

With-star delta starting method the delta connection has to be the "run voltage" , this motor would be seeing twice it's rated input voltage if delta connected to 460 volts, 460 volts can only be star connected to this motor.

 

[kwired]

and it gets better...
i was just told they had originally wired it as Delta and tried to start it yesterday.
instantly blew a 400A main breaker in the building.
double checked their wiring and started it again, ran for 3 minutes and blew a fuse (class J) at the local disconnect.
then they tried to wire it to Wye configuration and it just hums and wont start now. and they cant find a megger to test it...

As per my last post - you were applying about twice rated voltage if 460 and delta configuration.

Bet you (they) toasted it. might not even need megger, simple continuity test may show open coil(s)

 

[bwat]

we got a very expensive custom Siemens motor...

i was just told they had originally wired it as Delta and tried to start it yesterday.
instantly blew a 400A main breaker in the building.
double checked their wiring and started it again, ran for 3 minutes and blew a fuse (class J) at the local disconnect.
then they tried to wire it to Wye configuration and it just hums and wont start now. and they cant find a megger to test it...

That sounds like an expensive and hard to explain "whoops"..

 

[emiller233]

It is typical of IEC motors, you connect them wye for the higher voltage and delta for the lower voltage.

Star-delta is a starting method for when you want to reduce the instantaneous current upon energizing, would generally only be used on maybe 50 or more HP motors and needs more than just a three pole contactor for a controller.

With-star delta starting method the delta connection has to be the "run voltage" , this motor would be seeing twice it's rated input voltage if delta connected to 460 volts, 460 volts can only be star connected to this motor.

i've never actually used a star-delta setup, so that's helpful info! this is a 75HP motor

 

[emiller233]

As per my last post - you were applying about twice rated voltage if 460 and delta configuration.

Bet you (they) toasted it. might not even need megger, simple continuity test may show open coil(s)

i told him to try it with a regular met, said it went to 27ohms for a split second then to zero ohms....

 

[emiller233]

That sounds like an expensive and hard to explain "whoops"..

you ain't shitting...! i think the motor was $12K and took a year to get. annnnnd we'll need the repair of said motor expedited, so even more $$$ ...

 

[kwired]

What is "custom" about it? Shaft size/length or specialty design such as splines on the shaft? Mounting method?

Appears to be same volts and speed as NEMA general purpose motors which are probably easier to get.

 

[emiller233]

What is "custom" about it? Shaft size/length or specialty design such as splines on the shaft? Mounting method?

Appears to be same volts and speed as NEMA general purpose motors which are probably easier to get.

all the above except for the mounting method i believe? i haven't dug into the mechanical side of it much, having enough excitement on the electrical side of things... haha
it eventually goes to India i think and they wanted it to match the motors that they already have there, for whatever reason. which i think is for having spare parts that are 'readily accessible', which one would think should typically steer you Away from a large custom made motor...?
info is scarce on this project, we had no idea what they were sending us until the truck unloaded it into our shop

 

[Besoeker3]

all the above except for the mounting method i believe? i haven't dug into the mechanical side of it much, having enough excitement on the electrical side of things... haha
it eventually goes to India i think and they wanted it to match the motors that they already have there, for whatever reason. which i think is for having spare parts that are 'readily accessible', which one would think should typically steer you Away from a large custom made motor...?
info is scarce on this project, we had no idea what they were sending us until the truck unloaded it into our shop

That would explain it...............

 

[ActionDave]

and it gets better...
i was just told they had originally wired it as Delta and tried to start it yesterday.
instantly blew a 400A main breaker in the building.
double checked their wiring and started it again, ran for 3 minutes and blew a fuse (class J) at the local disconnect.
then they tried to wire it to Wye configuration and it just hums and wont start now. and they cant find a megger to test it...

i told him to try it with a regular met, said it went to 27ohms for a split second then to zero ohms....

You now have a very expensive boat anchor.

Whoever hooked that motor up delta was more than wrong, he was ignorant and dangerous.

 

[emiller233]

You now have a very expensive boat anchor.

Whoever hooked that motor up delta was more than wrong, he was ignorant and dangerous.

this one weighs 1,400lbs. its a little to big for my boat! haha

the hydraulic technician is usually the one that wires them up when he goes to test the system , wasn't sure so he walked over asked the electrical shop supervisor, and he's the one that told them to wire it Delta originally... he'll likely be having an exciting conversation later today...

but on the up and up side... it is getting torn off the machine as we speak and they're taking it to a siemens authorized repair shop this afternoon. Could get a little pricey $$$$

 

[Frank DuVal]

Cheaper and quicker than ordering a NEW one!

 

[winnie]

i've never actually used a star-delta setup, so that's helpful info! this is a 75HP motor

To add to what kwired said, the 'star' connection is the high voltage connection, and the delta is for low voltage operation. With a star/deta starter, the motor is operated at its _lower_ rated voltage, and temporarily connected using the high voltage configuration. This has the effect of operating the motor at a bit more than _half_ its rated voltage, dropping both starting torque and starting current. After the motor is up to reasonable speed it is reconnected in the delta configuration, thus operating at full rated voltage.

Star/delta starting only makes sense for variable torque loads such as fans, where the starting torque requirement of the mechanical load is low. Torque scales as the square of the supply voltage, so a star/delta starter means you only have 1/3 starting torque available.

-Jon

 

[Hv&Lv]

this one weighs 1,400lbs. its a little to big for my boat! haha

the hydraulic technician is usually the one that wires them up when he goes to test the system , wasn't sure so he walked over asked the electrical shop supervisor, and he's the one that told them to wire it Delta originally... he'll likely be having an exciting conversation later today...

That makes no sense that the hydraulic guy wires them up..
The electrical supervisor? If he was really a supervisor he would have been supervising and not letting the hydraulic technician wire them up.
Did the electrical supervisor even go look at the motor or just flippantly tell him to wire it delta?

 

[paulengr]

While you are at it you obviously got hold of an IEC world standard motor. So let’s just guess FLA is about 85 A. That means locked rotor will be around 510 A for a couple seconds but that isn’t what tripped your main. These things hit over 20 times FLA or almost 2000 A inrush. If your breaker instantaneous is set low it will probably trip even if the fuse is current limiting.

Make friends at the motor shop. They will give you a booklet that has all the wiring charts for standard motors for free. There are 2 standard ways to correctly wire a 6 lead motor. There are about two dozen ways to wire it up total. Some work, some do nothing, some destroy it. Follow the book every time.

On six lead single voltage motors watch out and check the manufacturer diagrams. Most use the high voltage wiring diagram only. But at least one (Toshiba) does not.

Finally do not make bastard motors. Lead times are so long you can only rewind and with today’s energy efficient motors the laminations are getting so thin even with temperature controlled burnout the number of rewinds is limited. There are plenty of standard sizes to pick from.

 

[emiller233]

That makes no sense that the hydraulic guy wires them up..
The electrical supervisor? If he was really a supervisor he would have been supervising and not letting the hydraulic technician wire them up.
Did the electrical supervisor even go look at the motor or just flippantly tell him to wire it delta?

i agree, but that's how this place has always operated here... the electrical dept is semi-new (like 8 years). but anywho, the hyd technician is pretty damn smart electrically. i highly doubt the electrical guys even went over and looked at it (guessing?)