Installation 2-3
Instruction Manual
Mounting
The drive must be mounted in the vertical position (heat sink fins must be vertical) away from
other heat producing devices. In multiple axis applications, a minimum of 1 inch separation
between each chassis is recommended. See Figure 7.1 on page 7-1.
Transformer Sizing
The MAX-430 requires an isolation/step-down transformer. To size a transformer for a MAX-
430 the power output (KVA) of each axis must be known. This can be derived by calculating the
horsepower for each axis.
Transformer single phase KVA rating = (Sum of each motor’s average output power) x 2.0
If you are using the Electro-Craft system sizing program (Systex), the average speed and average
torque data has already been calculated and can be used in the above equation.
Example
:
You are using a MAX-430 drive and 0644-35-021 motor, and you are unsure of the exact speed
and torque in your application. Look at the speed/torque curve for your drive/motor combi-
nation as shown in the Electro-Craft catalog and use the values for the worst case continuous
speed and torque.
Transformer single phase KVA rating = (Sum of each motor’s average output power) x 2.0
KVA =
Select a transformer that can provide enough voltage for the application. This can be determined
by looking at the maximum speed of the application and the voltage constant (K
E
) of the motor
selected.
TIP
The factor of 2.0 is used as an estimate of drive module and motor losses
.
KVA
Speed Torque
×
63 025
,
--------------------------------------
746 Watts
HP
------------------------
×
KVA
1,000 Watts
-----------------------------
×
2.0
×
=
Speed is in units of RPM
Torque is in units of lb-in
2000 RPM 6.2 lb-in
×
63 025
,
-----------------------------------------------------
746 Watts
HP
------------------------
×
KVA
1,000 Watts
------ --------------------- --
2.0
××
Transformer size = 0.294 KVA
K
E
Max Speed
×
1000
,
----------------------------------------
Motor Winding Resistance Peak Current
×()
+1.5
×
DC bus voltage=
K
E
= Volts/krpm
Max. Speed = krpm
Motor Windin
Resistance = Ohms
Peak Current = Amps
1.5 = 50% safet
and losses
Tapped voltage from transformer
DC bus voltage
2
-------------------------------------
≥
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