Parameter x.00
Parameter
protocol
Performance
structure
description
format
The
motor
is
modelled
thermally
in
a
way
that
is
equivalent
to
the
electrical
circuit
shown
below.
I
/(1.20
x
Field
Rated
Current)
2
See
Pr
5.81.
With
a
2Q
drive,
the
motor
can
be
driven
in
both
the
forward
and
reverse
directions
by
changing
the
polarity
of
voltage
applied
to
the
field.
This
mode
Parameter
Keypad
and
Advanced
parameter
descriptions
Serial
comms
Menu
5
=
RC
2
C
R
Temp
The
temperature
of
the
field
as
a
percentage
of
maximum
temperature,
with
a
constant
current
magnitude
of
I
and
constant
value
of
field
rated
current
(set
by
Pr
5.70
{SE10,
0.31}
or
Pr
21.24)
after
time
t
is
given
by
Temp
=
[I
2
/
(1.20*Field
rated
current)
2
]
(1
-
e
-t/
)
x
100
%
This
assumes
that
the
maximum
allowed
field
temperature
is
produced
by
1.20
x
field
rated
current
and
that
is
the
thermal
filter
of
the
point
in
the
motor
that
reaches
it
maximum
allowed
temperature
first.
is
defined
by
Pr
5.81.
The
estimated
motor
temperature
is
given
by
Pr
5.82
as
a
percent-
age
of
maximum
temperature.
If
the
Pr
5.81
has
a
value
between
0.0
and
1.0
the
thermal
filter
is
taken
as
1.0.
When
the
estimated
temperature
reaches
100
%
the
drive
stops
the
motor
and
then
trips
on
F.OVL.
The
time
for
some
action
to
be
taken
by
the
drive
from
cold
with
constant
field
current
is
given
by:
T
trip
=
-(Pr
5.81)
x
ln(1
-
(1.20
x
Pr
5.70
{SE10,
0.31}
/
Pr
5.56
{di09,
0.44})
2
)
Alternatively
the
thermal
filter
can
be
calculated
from
the
trip
time
with
a
given
current
from
Pr
5.81
=
-T
trip
/
ln(1
-
(1.20
/
Overload)
2
)
For
example,
if
the
drive
should
trip
after
supplying
125
%
overload
for
60
seconds
then
Pr
5.81
=
-60
/
ln(1
-
(1.20
/
1.25)
2
)
=
24
The
thermal
model
temperature
accumulator
is
reset
to
zero
at
power-up
and
accumulates
the
temperature
of
the
field
while
the
drive
remains
pow-
ered-up.
Each
time
Pr
11.45
is
changed
to
select
a
new
motor,
or
the
rated
current
defined
by
Pr
5.70
{SE10,
0.31}
or
Pr
21.24
(depending
on
the
motor
selected)
is
altered,
the
accumulator
is
reset
to
zero.
of
operation
can
be
achieved
using
a
2Q
drive
and
an
external
field
controller.
The
flux
in
the
field
cannot
be
reduced
until
the
motor
has
stopped.
The
time
taken
for
the
motor
direction
to
change,
will
depend
on
how
quickly
the
field
flux
can
be
reversed.
Figure
5-18
and
Figure
illustrate
the
sequence
of
events
during
a
forward
to
reverse
and
reverse
to
forward
change
of
direction.
Mentor
MP
Advanced
User
Guide
93
Issue
Number:
4
www.onxcontrol.com
5.81
Field
thermal
filter
Coding
Bit
SP
FI
DE
TE
VM
DP
ND
RA
NC
NV
PT
US
RW
BU
PS
1
1
1
1
Range
0.0
to
3000.0
Default
24.0
Second
motor
parameter
Pr
21.30
Update
rate
Background
read
5.83
Field
reversal
enable
Coding
Bit
SP
FI
DE
TE
VM
DP
ND
RA
NC
NV
PT
US
RW
BU
PS
1
1
1
1
1
Range
0
to
ONLY_2_QUADRANT
Default
0
Update
rate
Background
read
5.82
Field
overload
accumulator
Coding
Bit
SP
FI
DE
TE
VM
DP
ND
RA
NC
NV
PT
US
RW
BU
PS
1
1
1
1
1
Range
0
to
100.0
%
Update
rate
Background
write
