460
TECHNICAL REFERENCE
June 1999
96-8000
12.10 SPINDLE D RIVE A SSEMBLY
The spindle drive is located in the main cabinet on the right side and halfway down. It operates from three-
phase 200 to 240V AC. It has a 10 (or 20) H.P. continuous rating, and a 15 (or 30) H.P. one-minute rating. The
spindle drive is protected by CB1. Never work on the spindle drive until the small red CHARGE light goes out.
Until this light goes out, there are dangerous voltages inside the drive, even when power is shut off.
For all other data on the spindle drive, refer to the supplied documentation for your drive.
HAAS V ECTOR D RIVE
The Haas vector drive is a current amplifier controlled by the Mocon software, using the C axis output. The
vector drive parameters are a part of the machine parameters and are accessible through the Haas front panel.
The spindle encoder is used for the closed loop control and spindle orientation, as well as rigid tapping if the
option is available. Spindle speed is very accurate, since this is a closed loop control and the torque output at
low speeds is superior to non vector drive spindles.
12.11 RESISTOR A SSEMBLY
The Resistor Assembly is located on top of the control cabinet. It contains the servo and spindle drive regen
load resistors.
SPINDLE D RIVE R EGEN R ESISTOR
A resistor bank is used by the spindle drive to dissipate excess power caused by the regenerative effects of
decelerating the spindle motor. If the spindle motor is accelerated and decelerated again in rapid succession
repeatedly, this resistor will get hot. In addition, if the line voltage into the control is above 255V, this resistor
will begin to heat. This resistor is overtemp protected at 100
0
C. At that temperature, an alarm is generated and
the control will begin an automatic shutdown. If the resistor is removed from the circuit, an alarm may subse-
quently occur because of an overvoltage condition inside the spindle drive.
SERVO D RIVE R EGEN R ESISTOR
A 25-ohm, 300-watt resistor is used by the brush-type servo drives to dissipate excess power caused by the
effects of decelerating the servo motors. If the servo motors are accelerated and decelerated again in rapid
succession repeatedly, this resistor will get hot. In addition, if the line voltage into the control is above 255V,
this resistor will begin to heat. This resistor is overtemp protected at 100
0
C. At that temperature, an automatic
control shutdown is begun. If that resistor is removed from the circuit, an alarm may subsequently occur
because of an overvoltage condition for the servo buss.
OVERHEAT S ENSE S WITCH
There is an over-temperature sense switch mounted near the above-mentioned regen resistors. This sensor is a
normally-closed switch that opens at about 100
0
C. It will generate an alarm and all motion will stop. After the
time period, specified by parameter 297, of an overheat condition, an automatic shutdown will occur in the
control.