User manual

3U Servo Amplifier
over size to keep the impedances of these inserted devices from affecting stated system performance. In
general, it is recommended that all single-phase systems up to 1kW be designed for a 50% overload. All
single-phase systems over 1kW should be designed for a 200% overload capacity.
Noise Problems
When problems do occur often it points to electrical noise as the source of the problem. When this
occurs, turn to controlling high-frequency current paths. If following the grounding instructions does not
work, insert chokes in the motor phases. These chokes can be as simple as several wraps of the individual
motor leads through a ferrite ring core (such as Micrometals T400-26D). This adds high-frequency
impedance to the outgoing motor cable thereby making it harder for high-frequency noise to leave the
control cabinet area. Care should be taken to be certain that the core’s temperature is in a reasonable
range after installing such devices.
Operating Temperature
It is important that the ambient operating temperature of the 3U Geo Direct PWM drive must be kept
within specifications. The 3U Geo Direct PWM drive should be installed in an enclosure such as a
NEMA spec. cabinet. The internal temperature of the cabinet must be kept under the Geo Drive Ambient
Temperature specifications. It is sometimes desirable to roughly calculate the heat generated by the
devices in the cabinet to determine if some type of ventilation or air conditioning is required. For these
calculations the 3U Geo Direct PWM drive’s internal heat losses must be known. Budget 100W per axis
for 1.5A drives, 150W per axis for 3A drives, 200W per axis for 5A drives, 375W per axis for 10A
drives, 500W per axis for 15A drives, and 650W per axis for 20A drives (A are for continuous rating).
From 0°C to 45°C ambient no de-rating required. Above 45°C, de-rate the continuous and peak output
current by 2.5% per °C above 45°C. Maximum ambient is 55°C.
Backplane Board 10