# HELP ; Interpreting electrical diagram.

#### myfaithnka

Can anyone please help me understand the type of motor used here and how this electrical wiring works.

#### KlausST

##### Super Moderator
Staff member
Hi,

The type of motor is written next to it.
Voltage, power, 2x RPM, wiring. What else do you need?

The schematic is only a part of the whole...
We see the wiring, but notvwhy it's wired this way.
So - to avoid a lot of guessing - tell us what the whole machine is and does.

Klaus

#### myfaithnka

Hi Klaus,

Please find the machine's commercial flyer.

This is a strapping machine with two strap hands. This motor brings the strapping hands up and down.

Currently, one hand stopped working and I am trying to fix it. So while referring to this electrical diagram I could not understand how the setup works, I see YY written what does it mean, guessing it's not a normal 3 phase wye connected motor or 3 phase Delta connected motor. The conductor arrangements, hybrid motor starter, and two sets of 3 phase power lines, I am a little confused here.

could you please tell me how this wiring works for the motor at two speeds.

nithin

#### KlausST

##### Super Moderator
Staff member
Hi,

In the motor informations you see it is a "two RPM" type. It uses 6 wires (two winding sets) to set the desired RPM.

Each winding set is internally wired as wye.

Do an internet search for "dahlander" motors.

****
For debugging: step by step
* use a DVM to follow the voltages.
* check fuses for continuity (not powered)
* check to motor protection relay for continuity (not powered)
Mind: motor winding resistance may give a "wrong continuity"

Can you do live (powered) measurement?
Then an AC voltage measurement across a closed relay contact should clearly show close to "0V" (let's say below 0.5V)..non fluctuating.
Across an open contact it should show >> 0.5V. It may be 230V AC or fluctuating values

Klaus

myfaithnka

### myfaithnka

points: 2

#### myfaithnka

Hello Klaus,

I just want to confirm this is the motors internal diagram.

I just wanted to confirm the working of the wiring as following we have three mutually exclusive ways of motor operation.

1. The motors U1-V1-W1 windings energized by Contactor 161k07.
2. The motors U1-V1-W1 windings energized by Hybrid motor starter 160k10.
3. The motors U2-V2-W2 windings energized by 161k04 contactor and while this is done its auxiliary contacts shorts the windings U1-V1-W1.

yes I can do Live measurement using an EVM, I will update you soon.

#### FvM

##### Super Moderator
Staff member
I just want to confirm this is the motors internal diagram.

I just wanted to confirm the working of the wiring as following we have three mutually exclusive ways of motor operation.

1. The motors U1-V1-W1 windings energized by Contactor 161k07.
2. The motors U1-V1-W1 windings energized by Hybrid motor starter 160k10.
3. The motors U2-V2-W2 windings energized by 161k04 contactor and while this is done its auxiliary contacts shorts the windings U1-V1-W1.
I think mostly correct, except for
- there's probably no common star point (why should it?)
- if you read the schematic thoroughly, you notice that 161k07 runs the motor slowly backwards and 160k10 (slowly) forward

I guess that fast motor run by 161k04 is activated after starting through 160k10

What else are you missing?

I believe the motor connection doesn't fit Dahlander, it looks like a different kind of pole changing scheme.
--- Updated ---

O.K., I see Klaus is right though, winding connection in Dahlander circuit can be like this

Slow operation by powering UVW1, fast operation by powering UVW2, shorting UVW1.

Last edited:
myfaithnka

points: 2