Gold Whistle Servo Drive Complete Guide

7.2 Partition Layout Principles (Figure 4)

The PCB should be divided into two areas:

Power zone: including VP+, PR, PE, VL+, and motor output lines. These lines should be as wide and short as possible to avoid crossing with control signals.

Control and communication area: including feedback, I/O, USB, RS-232, EtherCAT, CAN, etc. These signals should be kept away from the power line and provide a complete reference plane on the ground plane.

7.3 Grounding and Return

PR (Power Return): It is the current circuit for the main power supply and motor, and must use a low impedance plane, preferably a complete ground plane layer.

COMRET (Control Common Terminal): Connect all low-level references of control signals. COMRET must be connected to PR at a single point on the integrated board (see Figure 3).

PE (protective grounding): connected to the casing and safety ground. There must be no connection between PE and PR on the PCB (voltage isolation). PE wiring only conducts electricity during abnormal faults.

Grounding error case: Connecting COMRET directly to PE resulted in a control circuit grounding loop, causing noise false triggering. The correct approach is to connect COMRET to PR, and then connect PR to PE through a high resistance resistor (such as 1   M Ω) and a parallel capacitor (such as 10   nF). However, according to safety regulations, PE and PR should be directly connected externally. In fact, Figure 3 shows that PE is externally connected to the ground, and PR is directly connected to the PE bypass? More accurate: Insulation must be maintained between PR and PE, and only a capacitor (Y capacitor) is connected between the ground and PR on the power supply side. It is recommended to strictly follow the grounding topology in the hardware manual.

Heat dissipation design

8.1 Thermal data

The thermal resistance (from the radiator to the environment) is approximately 10 ° C/W.

The thermal time constant is about 240 seconds (reaching 2/3 of the final temperature rise in 4 minutes).

Shutdown temperature: The radiator temperature is between 86 ° C and 88 ° C.

8.2 Do you need an external radiator?

Use the provided power consumption chart (Chapter 11) to evaluate:

Set the maximum radiator temperature to 80 ° C.

Measure the maximum ambient temperature (e.g. 40 ° C), allowing a temperature rise of Δ T=40 ° C.

Find the power consumption Pd (W) based on the working voltage and output current curve.

If Pd ≤ 4   W, no additional heat sink is required (relying solely on natural convection). If Pd>4   W, a heat sink needs to be installed (Elmo provides model WHI-HEAT-SINK-2).

Engineering experience: Actual testing shows that typical power consumption is 30% to 50% lower than the theoretical value in the chart, so the margin can be appropriately relaxed. But in a sealed case, the ambient temperature may be much higher than 40 ° C, so it must be measured.

Common fault codes and troubleshooting (based on EASII software)

Types of faults, possible causes, and solutions

Main power supply undervoltage VP+voltage below 12V, check power output; Increase capacitor holding voltage

Check if the main power supply is stable when the overvoltage VP+exceeds the upper limit (95V or 195V); Is there regenerative energy to lift the busbar

Overcurrent (instantaneous) motor short circuit, phase to phase short circuit, Hall commutation error, disconnect the motor, and measure the motor winding resistance with a multimeter; Reset and change phase angle

Overcurrent (effective value): Excessive load and steep acceleration/deceleration increase the acceleration/deceleration time; Reduce load; Choose a higher current model

Overheating (radiator) with insufficient heat dissipation and high ambient temperature, installing radiator/fan; Clean up dust; Reduce current limit

Encoder fault signal loss, CRC error check cable connection; Reduce communication speed; Replace the encoder

STO triggers the safety circuit to disconnect and reset the safety relay; Check the integrity of STO signal

Bus communication timeout (EtherCAT) synchronization loss, network cable disconnection check network topology; Increase watchdog time; Restart the main station

Debugging and software tools

Elmo Application Studio (EASII) is the official configuration, debugging, and diagnostic tool. After connecting via USB or RS-232, you can:

Automatically identify drive model and firmware version.

Motor parameter configuration (select motor type, number of poles, encoder resolution).

Autotune the current loop, speed loop, and position loop.

A real-time oscilloscope (Scope) collects waveforms such as current, velocity, position, and tracking error.

Fault history and export.

Initialization steps:

Hardware installation and power on.

Run EASII and connect to the drive.

Execute 'New Project', select motor model or manually input parameters.

Perform 'current loop self-tuning' (measure motor resistance and inductance).

Perform 'speed loop self-tuning' (automatically optimize PI parameters).

Save parameters to non-volatile memory.

Tip: When encountering difficult faults, using EASII's "recorder" function to capture data from the first few seconds of the fault can effectively locate occasional issues.