Maintenance & Reliability

Cross-Referencing: 4 Steps to Sizing an AC or DC Drive

Written by Galco | Aug 20, 2025

Supply chain issues have created challenges in parts replacement. But what happens when a drive needs to be replaced due to malfunction, or a drive needs to be added due to expansion, and that drive is unavailable?

Ideally, when a drive needs to be replaced, you simply reorder it by using the manufacturer and model or part number of your existing drive. Looking for a replacement AC drive or DC drive that is not available can be frustrating, and, more importantly, can result in costly downtime. This is where cross-referencing can help get you and your motor up and running again. 

What is Cross-Referencing?

Cross-referencing is the process of evaluating products to find equivalent products in each category using factors such as size, material, functionality, etc. For a successful cross-reference to happen, you must understand all these factors to know what will and will not work. 

In this case, we are looking for an equally or exceedingly high-quality, reliable, and dependable replacement drive by "crossing" it with your existing drive, motor, and application. The new drive that you get may not be the same brand. In many cases when a drive is crossed, the replacement drive, or new drive, may sometimes be a different brand.  

Cross-referencing is a great way to find a reliable and readily available replacement drive that meets or exceeds your and your application's needs. 

4 Steps to Sizing Your Drive for Cross-Referencing

Having the existing drive's part number alone is sometimes not enough. Each brand of drive may have something unique in its form, fit, and function, especially the one you are replacing. Essentially, you are sizing your drive to your application (motor) to ensure that the cross-referenced drive you select is the right solution. 

To help facilitate an efficient and successful cross-reference experience, we have broken this process down to the following four steps, or factors to be considered, each with a list of information needed to help get you back up and running quickly.  

STEP 1: Application Information

You will need this information for both AC and DC drives. 

FOR BOTH AC & DC DRIVES 

  • What is the application (pump, conveyor, etc.)? 
  • What is the input voltage? 

STEP 2: Motor Nameplate Data

To further help a successful cross-reference, the motor nameplate data is needed from the motor the drive is running.  

NOTE: AC and DC drives require different motor nameplate data.  

FOR AC DRIVES  FOR DC DRIVES 
Manufacturer  Manufacturer 
Part Number  Part Number 
Horsepower  Horsepower 
RPM  RPM 
Volts  Armature Volts 
Amps  Armature Amps 
Hz  Field Volts 
Insulation Class  Field Amps 
Service Factor  Ohms 

STEP 3: Existing AC or DC Drive Data

In addition to the motor nameplate data, you will want to have the following information about the AC or DC drive that you are cross-referencing. Since AC and DC drives come in a variety of shapes, sizes, and horsepower/voltage combinations, among others, this information is essential to completing a successful cross reference.  

NOTE: It is possible that not every item on this list pertains to your application and drive. 

FOR BOTH AC AND DC DRIVES 
Manufacturer 
Model/Part Number 
Size Restrictions 
Hight 
Width 
Depth 
Maximum RPMs 
Enclosure Information 
NEMA Rating? 
Environment/worst case ambient temperature? 
Distance
Between motor and drive DV/DT filter? 
Other safety impedance? 
Drive Control 
Keypad 
Mobile
Device 
Speed Potentiometer
DC Signal 
Fieldbus 
Speed Feedback Devices?
(Encoder, Tachometer, or Resolver
Type Manufacturer Model/Part Number Output Specifications 
Input/Output Requirements 
Digital Inputs 
Analog Inputs 
Digital Outputs 
Analog Outputs 
Relay Outputs 
Dynamic brake resistor
Interconnect prints? 
Fuse/Fuse blocks

STEP 4: Additional AC and DC Drive-Specific Factors

Depending on your application and system setup, you may have additional components and drive-specific factors. An AC or DC drive, even from the same manufacturer, may not come with the same features on every drive, and drives from other manufacturers may not either. This is why it is good to make note of as many details about your drive, motor, application, and any additional components or factors that are in play. Some, none, or all of these may or may not apply. Only address the ones that are applicable to your drive and application's specifications.

AC Drive  DC Drive 
Dynamic Brake
Bypass? 
Regenerative drive or non-regenerative drive? 
Output contactor? Reversing type? 

 

Now that you have the information needed to cross reference, you are ready to successfully replace the drive and one step closer to getting that motor running again. 

Any Questions? Contact Us! 

Our experts are equipped to help you find the right part you need and get it to you quickly. 

Call 800-575-5562 for additional assistance.