Yamaha RCX142, User Manual

Page: 44 / 450

3-
8
Installation
3
4. Connecting to the power
4.3 Installing an external leakage breaker
Since the robot controller drives the motors by PWM control of IGBT, leakage current
flows at high frequencies. This might cause the external leakage breaker to malfunction.
When installing an external leakage current breaker, it is important to choose the opti-
mum sensitivity current rating (I
∆
n). (Check the leakage breaker manufacturer’s data
sheets to select the optimum product compatible with inverters.)
R C X 1 4 2
R C X 1 4 2 - T
4 m A ( M A X )
2 m A ( M A X )
Leakage current
4.4 Installing a circuit protector
An inrush current, which might be from several to nearly 20 times higher than the rated
current, flows at the instant that the controller is turned on or the robot motors start to
operate. When installing an external circuit protector for the robot controller, select a
circuit protector that provides optimum operating characteristics.
To ensure proper operation, we recommend using a medium to slow response circuit
protector with an inertial delay function. (Refer to the circuit protector manufacturer’s
data sheets for making the selection.)
Example
R C X 1 4 2 2 0 A
R C X 1 4 2 - T 5 A
Rated current Operating characteristics
( )
Slow type with inertia delay
300% 2 sec.
1000% 0.01 sec.
4.5 Installing a current control switch
When controlling the power on/off of the robot controller from an external device such as
a PLC, a current control switch (contactor, breaker, etc.) may be used. In this case, the
current control switch usually creates a large on/off surge current. To minimize this on/off
surge current, surge killers must be installed for surge absorption. Connect a surge killer
in parallel with and close to each contact of the current control switch.
Recommended surge killer:
Okaya Electric XE1201, XE1202, RE1202 or equivalent
Example
: Surge killer
Controller
: Contactor
AC IN
FG
L
N
AC200V
c
CAUTION
1. Leak current was measured with
a leak tester with a low-pass filter
turned on (100Hz).
Leak tester: Hioki Electric 3283
2. When using two or more
controllers, sum the leakage
current of each controller.
3. Make sure that the controller is
securely grounded.
4. Stray capacitance between the
cable and FG may vary
depending on the cable
installation condition, causing
the leakage current to fluctuate.