Problem with a motor starter- 3phase 480 Volts

[Butter]

We are moving a hoist from a location in Pe. to our Ar shop. It was
supposedly in working order and when we tried to wire it up it is
malfunctioning. When you press either the up or down buttons
sometimes
nothing occurs and sometimes the coil of the contactor will
momentarily pull the contacts in but its just a quick in and an out.
This happens on both the up and down buttons.
Voltage to the unit was 480V and the only odd thing i found so far
is that the voltage coming off a transformer that should be 48V is
56V. This is what is going through the buttons to the coil of the
contactor. I have the wire diagram and everything seems to be ok. I
wondered if this could be caused by having a large voltage drop on
the
line that is only there after bushing in the buttons. When i push
buttons and it energizes the coil it kicks out to fast to notice if
the line voltage is dropping of if coil voltage is either.
Its also 97degrees here and this is all out in sun so I'd really
like to solve the problem
Ken

 

[Tom Biasi]

"Butter" <clannorm@yahoo.com> wrote in message
news:43e7b53e-aef0-4828-ae17-f9c766d40fa1@a36g2000yqc.googlegroups.com...

We are moving a hoist from a location in Pe. to our Ar shop. It was
supposedly in working order and when we tried to wire it up it is
malfunctioning. When you press either the up or down buttons
sometimes
nothing occurs and sometimes the coil of the contactor will
momentarily pull the contacts in but its just a quick in and an out.
This happens on both the up and down buttons.
Voltage to the unit was 480V and the only odd thing i found so far
is that the voltage coming off a transformer that should be 48V is
56V. This is what is going through the buttons to the coil of the
contactor. I have the wire diagram and everything seems to be ok. I
wondered if this could be caused by having a large voltage drop on
the
line that is only there after bushing in the buttons. When i push
buttons and it energizes the coil it kicks out to fast to notice if
the line voltage is dropping of if coil voltage is either.
Its also 97degrees here and this is all out in sun so I'd really
like to solve the problem
Ken

This is a basic electronics group. You really should contact someone
competent with this device. You can get fried.

Tom

 

[Jamie]

Butter wrote:

We are moving a hoist from a location in Pe. to our Ar shop. It was
supposedly in working order and when we tried to wire it up it is
malfunctioning. When you press either the up or down buttons
sometimes
nothing occurs and sometimes the coil of the contactor will
momentarily pull the contacts in but its just a quick in and an out.
This happens on both the up and down buttons.
Voltage to the unit was 480V and the only odd thing i found so far
is that the voltage coming off a transformer that should be 48V is
56V. This is what is going through the buttons to the coil of the
contactor. I have the wire diagram and everything seems to be ok. I
wondered if this could be caused by having a large voltage drop on
the
line that is only there after bushing in the buttons. When i push
buttons and it energizes the coil it kicks out to fast to notice if
the line voltage is dropping of if coil voltage is either.
Its also 97degrees here and this is all out in sun so I'd really
like to solve the problem
Ken
I suggest you change the pendant and its associated cable. Sounds like

a wire break in there somewhere.

 

[Jasen Betts]

On 2009-06-23, Butter <clannorm@yahoo.com> wrote:

We are moving a hoist from a location in Pe. to our Ar shop. It was
supposedly in working order and when we tried to wire it up it is
malfunctioning. When you press either the up or down buttons
sometimes
nothing occurs and sometimes the coil of the contactor will
momentarily pull the contacts in but its just a quick in and an out.

have you got the phases in the right order? (just a guess)

 

[George Herold]

On Jun 23, 4:14 pm, Butter <clann...@yahoo.com> wrote:

We are moving a hoist from a location in Pe. to our Ar shop. It was
supposedly in working order and when we tried to wire it up it is
malfunctioning. When you press either the up or down buttons
sometimes
nothing occurs and sometimes the coil of the contactor will
momentarily pull the contacts in but its just a quick in and an out.
This happens on both the up and down buttons.
  Voltage to the unit was 480V and the only odd thing i found so far
is that the voltage coming off a transformer that should be 48V is
56V. This is what is going through the buttons to the coil of the
contactor. I have the wire diagram and everything seems to be ok. I
wondered if this could be caused by having a large voltage drop on
the
line that is only there after bushing in the buttons. When i push
buttons and it energizes the coil it kicks out to fast to notice if
the line voltage is dropping of if coil voltage is either.
  Its also 97degrees here and this is all out in sun so I'd really
like to solve the problem
Ken

"Y" connection with the wrong wire grounded?
George H.