IAI RCM-P6AC, Instruction Manual

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1. Specifications Check
Fieldbus Communication
32
RCP6S
1.3 The Calculation of Number of Connectable Axes and Power Capacity
To calculate the number of axes connectable to one unit of the gateway unit and the current
amperage of 24V DC, figure out (1) to (4) below and follow (5).
(1) The Calculation of Number of Connectable Axes, and Motor Current Consumption
Condition 1: Sum total of motor current consumption connectable to one unit of hub unit: 12.8A
Condition 2: Number of controlled axes connectable to corresponding 1 unit: 4-axes or less
* By adjusting the number of connected axes or motor type, select the connected axes so each
hub unit satisfies the formulas below.
● Sum total of motor current consumption for hub unit= Motor current consumption of 1st axis
+ Motor current consumption of 2nd axes (if connected)
+ Motor current consumption of 3rd axes (if connected)
+ Motor current consumption of 4th axes (if connected) ≤ 12.8A
···········
1)
● Sum total of motor current consumption = Motor current consumption of hub unit 1st unit
+ Motor current consumption of hub unit 2nd units (if connected)
+ Motor current consumption of hub unit 3rd units (if connected)
+ Motor current consumption of hub unit 4th units (if connected)
··········
2)
(2) Control Power Current Consumption:
0.3A × Number of ac 0.6A (GW) + 0.3A × Number of hub unit
······································
3)
(3) Rush Current: 8.3A (RCP6S Motor type 28P, 35P, 42P, 56P and RCM-P6PC)
10A (RCP6S Motor type 56SP, 60P, RCM-P6AC and RCM-P6DC)
···················
4)
(4) (For RCP6S only) Current Consumption of Brake Release Power:
Number of actuators with brake × 0.7A
························
5)
* When servo is on, it should be 0.5sec or less, after that retaining of released status should be
0.1A / axis.
When using the control power source and the motor power source in common, calculate with
the number of brake-equipped actuators
×
0.1A.
(5) Selection of Power Supply:
Usually, the rated current is to be approximately 1.2 times higher than the total of Control Power
2) + 3) + 5) above considering approximately 30% of margin to the load current.
However, considering the inrush currents of 4), even though it is a short time, select a power
supply with “sufficient peak load capacity.
Avoid current of 4) from occurring at the same time by having the timing of emergency stop
release (turning the motor power on) and timing to turn the servo on shifted
(Note 1)
from each
other and so on. Huge current flow of the same time may cause a transient voltage drop.
Be careful especially when selecting a power source equipped with remote sensing.
Note 1 The timing to turn the servo on can be tuned in Parameter No. 165 [Latency after
Shutdown Release]
.
(Note) Ensure motor and control power supplies reference the same potential when using
multiple power supplies.
(Reference) Selection of Power Supply Protection Circuit Breaker
It is recommended that the power supply protection is conducted on the primary
side (AC power side) of the 24V DC power supply unit.
When selecting the protection breaker, consider the rated cutoff current of the
circuit breaker so a cutoff is surely performed even in the case of inrush current of
24V DC power supply unit or a short-circuit of the power supply.
• Rated Breaking Current > Short-circuit Current = Primary Power Supply Capacity
/ Power Voltage
• (Reference) In-rush Current of IAI Power Supply Unit PS241 = 50 to 60A, 3msec
ME0349-4B