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d. With the power off, check
motor heat sensor continuity.
e. Check wiring of mixer to
con trol panel. It should
agree with the sche mat ic.
2. Mixer does not run in Auto
position.
a. Check items (a.) through
(e.) per Item #1 above.
b. Check knob settings on
timer to ensure proper
sequencing. Check both On
and Off time range selector
knobs as well as On and Off
time adjustment knobs.
c. If mixer does not run in
Auto mode, check Auto
circuit wiring in panel.
3. Mixer runs, but run light
does not energize.
a. Re move light and check
with an ohmmeter.
b. Check run light wir ing.
4. Severe humming/chat ter ing
of control relay.
a. There may be low voltage.
Check voltage at primary
and secondary of control
transformer
us ing
volt me ter. This low voltage
condition may cause severe
chat ter ing and burnout of
relay.
b. Relay may have dust around
magnet of coil struc ture.
Dry or clean as re quired.
c. Check
voltage
control
panel.
require a minimum of
80% of full volt age to pull
in without chatter. If the
problem is a re cur ring
one, measure voltage with
recorder on a 24 hour basis.
d. Dry out the junction box
(if
furnished);
in the junction box may
cause relays to energize
intermittent ly.
5. Short cycling mixer.
a. Check timer controls.
6. Run light stays on.
a. Selector switch may be in
the Hand position.
7. Nuisance tripping of overload
on VFD or cir cuit break ers.
a. Check mixer amp draw with
amp probe and compare to
nameplate amps on mixer.
b. The propeller may be locked
up due to excessive debris
or solids.
c. Possible motor failure (fault
in windings).
d. Mixer may be miswired to
ter mi nal block.
e. Voltage
unbalance.
un balance
phase power sources can
cause motor current to
become un bal anced and
exces sive
re sult. Trip ping of the
over load protection and
premature motor failures
a
can be expected if the
current unbalance exceeds
five percent.
Percent
Current
=
Unbalance
to
the
To determine if motor current
Relays
un bal ance is a function of the
motor or the power supply:
1. Label the leads and the terminals
1, 2, and 3 respectively.
2. Record the amperage for each
lead.
3. Move each lead to the next
moisture
terminal (1 to 2, 2 to 3, 3 to 1).
and
current
Voltage
on
three
heating
will
Maximum Current
Difference from x 100
Average Current
_______________
Average Current
4. Again read the amperage of
each lead.
5. Move each lead to the next
terminal (1 to 3, 2 to 1, 3 to 2).
6. Again read the amperage of
each lead.
7. If the unbalance moves with
the motor leads, the un bal ance
is caused by the mo tor. If the
unbalance remains with the
terminals, the un bal ance is in
the pow er supply.
8. If
the
current
exceeds five percent, nui sance
tripping or ex ces sive heating
will result.
9. Connect leads for the lowest
percent of current un bal ance.
Factory Set
Parameters for VFD
Parameters set at factory for 230V panels
1) Set 1-20 motor power
2) Set 1-22 motor voltage
3) Set 1-24 motor current
4) Set 1-25 motor nominal speed
5) Set 3-02 min. speed in Hz
6) Set 3-03 max. speed in Hz
7) Set 3-15
8) Set 3-16
9) Set 3-41 ramp up time
10) Set 3-42 ramp down time
Parameters set at factory for 460V panels
1) Set 1-20 motor power
2) Set 1-22 motor voltage
3) Set 1-24 motor current
4) Set 1-25 motor nominal speed
5) Set 3-02 min. speed in Hz
6) Set 3-03 max. speed in Hz
7) Set 3-15
8) Set 3-16
9) Set 3-41 ramp up time
10) Set 3-42 ramp down time
unbalance
1.5 kW or 2 HP
230 volts
4.8 amps
1150
30
60
0
0
3.00 sec.
3.00 sec.
1.5 kW or 2 HP
460 volts
2.4 amps
1150
30
60
0
0
3.00 sec.
3.00 sec.
7
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