2198-C4020-ERS — Kinetix 5500 Capacitor Module, 400V, Shared DC Bus

The 2198-C4020-ERS is a capacitor module for the Kinetix 5500 servo drive family, designed for use in shared DC bus configurations. It doesn't drive a motor — its job is to store energy on the shared bus and release it during demand peaks, reducing the regenerative energy that would otherwise need to be dissipated through a braking resistor or returned to the AC supply.

In multi-axis systems where axes decelerate and regenerate simultaneously with other axes accelerating, much of the energy exchange happens within the DC bus rather than going back to the mains. The capacitor module extends this energy buffering capacity, smoothing the bus voltage during transient demand and allowing system designers to specify a smaller mains supply or avoid braking resistors entirely in applications with balanced energy profiles.

Specifications

Parameter	Value
Part Number	2198-C4020-ERS
Compatible Drive Family	Kinetix 5500
DC Bus Voltage	400V DC nominal
Capacitance	2000 μF (nominal)
Shared Bus Configuration	Yes (DC bus connector)
Regenerative Energy Storage	Yes
Safe Torque Off (STO) Support	Yes (ERS — Safe Speed Monitor)
Mounting	Panel mount, shared bus bar connection
Operating Temperature	0°C to 50°C
Standards	UL 508C, CE, IEC 61800-5-1

Shared DC Bus — How It Works in Practice

In a standard multi-axis Kinetix 5500 installation, each drive has its own AC-to-DC converter (rectifier) and its own DC bus capacitors. A shared DC bus configuration replaces or supplements the individual bus capacitors with a common bus that all drives in the group share.

When an axis decelerates, its drive regenerates energy back onto the shared bus. If another axis is simultaneously accelerating, it draws that energy directly from the bus rather than from the AC mains. The result is lower peak demand from the supply and reduced heat from braking resistors. The capacitor module adds bulk storage to the shared bus, increasing the time window over which this energy exchange can occur.

This matters most in applications with fast, repetitive motion cycles — pick-and-place robots, rotary indexers, flying shear drives — where axes are constantly accelerating and decelerating. The energy savings compared to individual drives with separate braking resistors can be substantial over a full production shift.

Things to Verify Before Installation

Confirm the DC bus voltage rating matches the Kinetix 5500 drives in the group — bus voltage is determined by the input AC supply, not the module itself.
The capacitor module must be positioned on the shared DC bus bar in the correct physical location relative to the drives — consult the Kinetix 5500 system wiring diagram for placement rules.
Bus bar connections must be torqued to specification. Under-torqued bus connections cause resistive heating at the joint that can damage the bus bar and the module connector over time.
DC bus pre-charge: the capacitors in the module will draw inrush current on first energization. The Kinetix 5500 system includes a pre-charge circuit, but verify it is operational before initial power-up.

FAQ

Q: Can this module be used with Kinetix 5700 drives?

No. The 2198 series is specific to Kinetix 5500. The Kinetix 5700 uses a different bus architecture and its own capacitor/bus supply modules from the 2198-CAPMOD range.

Q: Does adding this module eliminate the need for a braking resistor?

It depends on the application. In balanced systems where regenerative energy from decelerating axes is largely consumed by accelerating axes, the capacitor module can eliminate the need for braking resistors. In systems with net regeneration (more energy going back than is reused), a regenerative power supply or braking resistor is still needed to handle the excess.

Q: What does "ERS" mean on this module?

ERS stands for Safe Speed Monitor — a safety function that monitors motor speed and triggers a safe state if speed exceeds a configured limit. It is a functional safety feature that must be wired and configured as part of the machine's safety system design.

Q: How many capacitor modules can be added to one shared bus group?

The number is limited by the bus bar current capacity and the total inrush current during initial bus pre-charge. Kinetix 5500 system design guidelines define the maximum bus capacitance per group — exceeding this can stress the pre-charge circuit.

2198-C4020-ERS Brand New Kinetix 5300 Servo Drive 3.9 kW 2198C4020ERS