In the field of industrial automation, facing occasional failures of discontinued control modules (such as Woodward series) or safety systems (such as Honeywell), the most urgent need for engineers is to find a reliable, efficient, and safe alternative and solution in the shortest possible time. When faced with insufficient performance of existing drive systems, shortage of spare parts, or the need for functional upgrades, ServoOne single axis servo drives become an ideal replacement option with their modular design, powerful communication capabilities, and flexible motion control intelligence.
This article aims to provide a comprehensive technical guide on ServoOne drives for electrical engineers, maintenance technicians, and system integrators. We will refer to the practical logic of equipment replacement and troubleshooting, deeply analyze every key link from mechanical installation, electrical design, core parameter configuration to system diagnosis, to ensure that you can independently and safely complete project implementation.
Chapter 1: Project Preparation and Safety Guidelines - The First Line of Defense for Replacement Engineering
A rigorous risk assessment and preparation process is essential before any hardware replacement. This is not only a compliance requirement, but also the cornerstone for ensuring personal and equipment safety.
1.1 Safety regulations and responsibility definition
As a component in industrial and commercial systems, the ServoOne driver must strictly follow the relevant instructions during debugging. According to the manual, when the driver is integrated into the machine, it must be ensured that the machine fully complies with the 2006/42/EC Machinery Directive and must comply with the EN 60204 standard. For electromagnetic compatibility (EMC), the start-up operation must strictly comply with the 2004/108/EC EMC directive.
Core Security Tips:
High voltage hazard: The internal DC bus capacitor of ServoOne may still maintain a dangerous voltage above 50V for up to 30 minutes after power failure. The wiring operation can only be carried out after the voltage of the DC bus terminals (such as X12/L+and L - of BG1-BG4; X11/ZK - and X11/ZK+of BG7) has been measured to a safe range after power failure.
Rotating components: The drive may start automatically, and touching rotating components is strictly prohibited until mechanical safety is confirmed.
Responsibility attribution: The manual clearly states that electronic devices are not absolutely fail safe. The equipment operator is responsible for ensuring mechanical safety through external safety circuits (such as emergency stop systems) in the event of a drive failure.
1.2 Compatibility assessment for replacement
When starting to replace discontinued Woodward modules, it is necessary to verify the following core features of ServoOne:
Power range: covering 4A to 450A, supporting single-phase 230V to three-phase 480V wide voltage input.
Cooling method: Two options are available: air cooling (BG1-BG6a) and liquid cooling (BG3-BG7), depending on the cooling capacity of the original system cabinet.
Safety function: Built in STO (Safe Torque Off) function, compliant with EN ISO 13849-1 standard, can directly replace old modules that require such safety functions, simplifying external safety circuit design.

Chapter 2: Mechanical Installation and Cooling System Renovation
Physical installation is the first step in replacement work. Incorrect installation can lead to poor heat dissipation, EMC interference, and even device damage.
2.1 Installation environment requirements
Cabinet: ServoOne is designed specifically for installation inside fixed control cabinets. The cabinet protection level must be at least IP4x. If STO function is used, according to EN ISO 13849-2, the cabinet protection level must be raised to IP54 or higher.
Pollution level: The maximum allowable pollution level is level 2 (according to EN 60664-1).
Vibration resistance: Drivers should not be installed in environments with continuous vibration. The transportation vibration limit is detailed in Appendix Table A.18 of the manual.
2.2 Installation spacing and steps
The manual provides detailed mechanical drawings for all dimensions from BG1 to BG7 (Figure 2.1 to Figure 2.5). The key installation principles are as follows:
Vertical installation: The driver must be installed vertically on the mounting plate to ensure normal circulation of cooling air or even distribution of liquid coolant.
Spacing requirement: The minimum spacing "E" (such as 40mm for BG1-BG4) should be maintained between adjacent drivers to ensure heat dissipation. When installing different power devices side by side, they should be arranged in descending order of power (e.g. left to right: BG4-BG3-BG2-BG1) to minimize thermal effects.
Tightening torque: For liquid cooled equipment (such as BG7), when connecting the cooling circuit, a 22mm open-end wrench must be used to secure the pipe joint to prevent torque damage to the equipment.
2.3 Liquid cooling circuit connection (for BG3-BG7)