Installation And Operation; General Instructions - Hitachi HBU-2015 Instruction Manual

III. Installation and Operation
1. The inverter DC Bus can hold a dangerous electrical charge for some time after AC power
had been removed. Make sure that the inverter input power has been turned off for at least
10 minutes before you attempt to make any wiring connections to the HBU..
2. Wiring should be done by a licensed electrician following applicable codes and generally
accepted wiring practices.
3. Do not touch the terminals or internal components of the braking unit while the DC bus is
charged.
4. Make sure that no wire strands contact the metal case of the HBU, or cause a short circuit
between the terminals.
1. Be sure to connect the braking resistors, braking unit and inverter according to the
connection diagram.
2. Tighten the terminal screws according the specified torque.
A. General instructions
1. Use wire gauge > 4 mm
2. Check that the connections are correct before you connect to the power supply. Refer to the wiring diagram in
Figure 4 for the necessary connections for P and N, and recommended use of fault alarm functions. The terminal
arrangement is shown in Figure 7.
3. The HBU incorporates internal fault detection which can be monitored externally through the relay alarm output
terminals marked Tb and Tc. Should the HBU detect an internal fault, the relay will energize and the state of the
Tb/Tc output will change. These terminals should be wired to a safety circuit as appropriate. In the factory default
configuration, the Tb/Tc output will CLOSE when the HBU detects a high internal temperature, and will be
OPEN otherwise. An HBU fault will cause an external trip fault in the inverter. Note: Jumper J8 will change the
logic sense of the Tb/Tc output from NO to NC (Figure 5) should your system so require. However, it is
recommended to use the factory default setting as described. Refer to the Inverter Instruction Manual for more
specific details about how to wire and set up an external trip input.
4. The resistor(s) must incorporate an internal thermal switch (usually open-on-fault type), and this must be wired
with a safety circuit that will remove power to the inverter. A typical configuration is shown in Figure 4. In this
way, a resistor over-temperature condition, or a break in the alarm wiring, will cause power to be removed from
the inverter.
5. IMPORTANT NOTE: On 400 V models only, there are five voltage settings (630V, 660V, 690V, 730V, and 760V)
for unit activation. The braking voltage MUST be set to meet the needs of the application. Set the voltage by
moving the jumper on inside the HBU to the pair of pins that correspond to the activation voltage desired. Note:
14
WARNING!
CAUTION!
2
on power supply connection and resistor connection.
Hitachi America, Ltd.
Tarrytown, NY