Match the cord to both connection points: the source outlet and the equipment inlet. A server with a C14 inlet normally takes a C13 cord connector; when the PDU has a C13 outlet, the other end of that cord is a C14 plug. A server with a C20 inlet normally takes a C19 cord connector; a C19 PDU outlet takes a C20 plug. These are mating relationships, not complete electrical approvals.
A correct match also requires compatible supply voltage, equipment input requirements, cord-assembly ratings, regional approvals, temperature conditions, and any locking mechanism. Connector shape alone does not establish those conditions.
Identify the Outlet, Cord Ends, and Equipment Inlet
Describe each connection from the power source toward the equipment. This avoids the ambiguity of product descriptions such as “C13/C14 cable,” which may not explain which end goes where.
| Connection point | What it does | Common rack example |
|---|---|---|
| Source outlet or receptacle | Supplies power to a cord | C13 or C19 outlet on a rack PDU |
| Source-side cord plug | Inserts into the source outlet | C14 plug into C13; C20 plug into C19 |
| Equipment-side cord connector | Fits over the equipment inlet contacts | C13 connector onto C14; C19 connector onto C20 |
| Equipment inlet | Receives power into the equipment | C14 or C20 inlet on a server power supply |
The C13/C14 and C19/C20 mating pairs appear in Eaton’s rack PDU connector reference. The same designation can appear in different mounting arrangements: a C14 interface may be an equipment-mounted inlet or the source-side plug on a jumper cord. Identify its role as well as its designation.
For example, a complete server connection can be written as:
PDU C13 outlet → cord C14 plug — cable — cord C13 connector → server C14 inlet.
The PDU’s own input connection is a separate interface. Do not order server cords from the PDU input-plug specification.
IEC C13/C14 and C19/C20 Identification Reference
Use the molded designation, equipment documentation, and manufacturer drawing to identify an interface. Shape is a useful cross-check, but it should not replace the part marking.
| Interface | Contact arrangement and identification cue | Normal mating interface | Typical rack role |
|---|---|---|---|
| C13 | Female contacts; smaller housing with chamfered upper corners | C14 | PDU output outlet or equipment-side cord connector |
| C14 | Male contacts; corresponding chamfered profile | C13 | Server or network-device inlet; source-side jumper-cord plug |
| C19 | Female contacts; larger, more rectangular profile | C20 | PDU output outlet or equipment-side cord connector |
| C20 | Male contacts; corresponding larger rectangular profile | C19 | Equipment inlet; source-side jumper-cord plug |
Eaton’s illustrated reference shows these four interfaces and their regional rating categories. A standard C13 connector does not directly mate with a C20 inlet, and a standard C19 connector does not directly mate with a C14 inlet.
Connector ratings depend on the approval system
The same interface family can carry different current ratings under different regional approvals.
| Mating pair | IEC/European rating category shown in Eaton’s reference | North American rating category shown in Eaton’s reference |
|---|---|---|
| C13/C14 | 10 A, 250 V | 15 A, 250 V |
| C19/C20 | 16 A, 250 V | 20 A, 250 V |
These are reference categories—not a guarantee that every cord with those ends carries the maximum listed current. Use the applicable approval and rating of the actual purchased assembly.
The distinction is visible in component-level documentation. SCHURTER’s 4795 C19 connector lists an IEC rating of 16 A at 250 VAC, 50 Hz, and a UL/CSA rating of 20 A at 250 VAC, 60 Hz. Those are ratings for that connector under the stated approvals and conditions, not an automatic rating for a cord assembled around it.
A 250 V marking also does not identify the voltage actually present at a PDU outlet. Confirm the configured supply voltage and the equipment’s permitted input range separately.
Match the Cord to Both Ends
Choose the source-side plug from the outlet and the equipment-side connector from the inlet. The following table identifies physical connection paths; each selection still requires the electrical and installation checks below.
| Source outlet | Equipment inlet | Cord ends, source → equipment | Selection condition |
|---|---|---|---|
| IEC C13 | IEC C14 | C14 plug → C13 connector | Standard matching pair at each end |
| IEC C19 | IEC C20 | C20 plug → C19 connector | Standard matching pair at each end |
| IEC C19 | IEC C14 | C20 plug → C13 connector | Valid mixed-end cord arrangement; retain the assembly’s own current limit |
| NEMA 5-15R | IEC C14 | 5-15P plug → C13 connector | Equipment must accept the actual supply voltage |
| NEMA 5-20R | IEC C14 | 5-20P plug → C13 connector | Do not infer a 20 A cord rating from the source plug |
| NEMA L6-20R | IEC C20 | L6-20P plug → C19 connector | Verify equipment voltage requirements and the complete cord rating |
| NEMA L6-30R | PDU with an L6-30P input | PDU’s specified L6-30P input cord | This is the facility-to-PDU connection, not a server jumper |
The IEC pairings and NEMA plug/receptacle designations are shown in Eaton’s connector reference. Eaton also lists commercial C20-to-C13 and L6-20P-to-C19 cord arrangements.
A mixed-end cord does not inherit the larger connector’s rating
A C20-to-C13 cord can connect a C19 PDU outlet to a C14 equipment inlet. It does not make the equipment connection a 20 A path.
For example, Eaton’s P032-007 is specified as a C20-to-C13 cord rated 15 A, 100–250 V, with 14 AWG conductors and a length of 7 ft (2.13 m). The C20 end does not override the published 15 A assembly rating. That product rating also should not be transferred to a different cord with similar-looking ends.
The reverse situation—a C13 source outlet supplying equipment with a C20 inlet—requires particular care. A manufacturer-supplied C14-to-C19 assembly may exist, but its existence does not establish that the equipment is suitable for the lower-rated source path. Eaton lists a 15 A C14-to-C19 cord among its PDU accessories; selection still depends on the equipment’s permitted input configuration and current requirement.
Do not use an adapter merely to bypass a connector mismatch without resolving why the equipment and source use different interfaces.
Common North American NEMA Connections
The following configurations are common in North American rack-power connections. They are not a global receptacle reference.
In NEMA designations, P identifies a plug, R identifies a receptacle, and an initial L identifies a locking configuration. Thus, L6-30P is a locking plug, while L6-30R is its corresponding receptacle.
| NEMA configuration | Device rating | Mechanical style | Corresponding connection |
|---|---|---|---|
| 5-15 | 15 A, 125 VAC | Straight blade | 5-15P plug and compatible receptacle |
| 5-20 | 20 A, 125 VAC | Straight blade | 5-20P plug and 5-20R receptacle |
| L5-20 | 20 A, 125 VAC | Locking | L5-20P and L5-20R |
| L5-30 | 30 A, 125 VAC | Locking | L5-30P and L5-30R |
| L6-20 | 20 A, 250 VAC | Locking | L6-20P and L6-20R |
| L6-30 | 30 A, 250 VAC | Locking | L6-30P and L6-30R |
Eaton’s wiring-device catalog gives these device ratings; its rack PDU reference illustrates the plug and receptacle configurations.
Keep device voltage ratings separate from nominal operating voltage. Eaton’s rack reference associates common 5-series applications with 120 V and common L6 rack applications with 208 V, while the corresponding wiring devices are rated 125 V and 250 V respectively. Neither number alone identifies the actual voltage at a particular outlet.
Do not substitute L5 for L6, or a 20 A locking configuration for a 30 A locking configuration. Match the full designation rather than only the current number or the presence of curved blades.
Separate PDU Input Matching From PDU Output Matching
A rack PDU can have one connector family at its input and several different output interfaces.
For a concrete example, Eaton’s PDUMVR30HVNETLX product page specifies:
- An L6-30P input plug.
- Twenty C13 output outlets.
- Four C19 output outlets.
- A 208/230 V operating specification and a 24 A PDU current rating.
Its connection paths are therefore:
Facility L6-30R receptacle → PDU L6-30P input plug → PDU.
PDU C13 outlet → C14-to-C13 cord → equipment C14 inlet.
PDU C19 outlet → C20-to-C19 cord → equipment C20 inlet.
The L6-30 input designation does not make every output outlet a 30 A connection. Likewise, the presence of both C13 and C19 outlets does not establish different output voltages or imply voltage conversion. Use the exact PDU model’s electrical specifications and installation instructions to establish what each outlet supplies.
This distinction lets purchasing teams answer two different questions without mixing them: “Will the PDU connect to the facility receptacle?” and “Which cords connect the equipment to the PDU?”
Check Electrical and Mechanical Conditions Before Ordering
Supply voltage and equipment input
Record the actual supply voltage and frequency, then compare them with the installed power supply’s nameplate and manual. Use the power-supply model, not only the server chassis model: a chassis may be offered with different power-supply options.
Do not assume that a C14 or C20 inlet means the equipment accepts every voltage used with that connector family. If the power supply’s permitted voltage range is unknown, connector identification alone cannot resolve suitability.
Complete cord-assembly rating
Obtain the manufacturer’s rating for the complete cord, including its applicable regional approval. Record the conductor size and jacket type, but do not derive an approved assembly rating from AWG alone.
Eaton’s locking-cord catalog, for example, lists C14-to-C13 assemblies at both 10 A with 18 AWG conductors and 15 A with 14 AWG conductors. Similar endpoint designations therefore do not establish identical cord ratings.
The cord rating must suit the equipment’s required input current under the intended operating conditions. Outlet-group capacity, branch-circuit loading, protective-device selection, and redundancy behavior remain separate checks; a connector table does not resolve them.
Temperature and inlet type
Check the equipment’s specified connector type and temperature requirements. Do not replace a specified higher-temperature connector with a C13 merely because the interfaces appear similar.
Also distinguish contact-temperature conditions from ambient-temperature limits. SCHURTER’s 4795 documentation identifies a 70°C pin-temperature condition and separately lists an allowable operating-temperature range of −25°C to 70°C. These are product-specific conditions, not universal temperature limits for every C19 cord or every rack installation.
Locking and retention compatibility
A locking IEC cord needs a compatible retention system. “Locking C14” or “locking C20” is not enough information to establish that a particular PDU will engage the latch.
Eaton specifies P-Lock C14 cords for P-Lock-compatible C13 or C39 outlets, and P-Lock or P-Lock Lite C20 cords for compatible C19 or C39 outlets. Verify the exact cord and PDU combination rather than assuming interchangeability between retention systems.
Some combination outlets accept more than one plug type. Eaton’s C39 outlet, for example, accepts both C14 and C20 plugs. Treat that as a documented feature of the specified outlet—not a property of ordinary C13 or C19 outlets.
Length, orientation, and service access
Measure the intended routed path, including cable-management arms and necessary service movement. Specify the shortest practical length that avoids tension and still allows the equipment to be serviced.
For right-angle connectors, approve a manufacturer drawing showing cable-exit direction relative to the inlet and adjacent hardware. “Left,” “right,” “up,” and “down” can be ambiguous when supplier drawings use different viewing directions.
Confirm that the connector body, latch, and cable bend do not obstruct adjacent outlets, power-supply handles, or removal access.
Procurement Checklist
Create one line item for each distinct cord assembly. Use the following fields to make the purchase specification reviewable.
| Field | What to record |
|---|---|
| Equipment identification | Device model, installed PSU model, and inlet designation |
| Source identification | PDU model, outlet designation, and assigned outlet or group |
| Source-side cord end | Exact plug designation and required locking system |
| Equipment-side cord end | Exact connector designation, retention requirement, and exit orientation |
| Electrical conditions | Actual supply voltage and frequency; equipment’s permitted input and required current |
| Assembly ratings | Published cord current and voltage ratings, applicable approvals, and manufacturer part number |
| Cable construction | Conductor count and size, jacket designation, and specified temperature conditions |
| Routing | Required length, connector clearances, support, and service movement |
| Feed identification | Equipment PSU label, PDU asset ID, outlet ID, and A/B feed designation where applicable |
| Quantity | Number of verified connections using that exact assembly |
For redundant power supplies, document each connection independently. Different cord colors can help trace A and B feeds, but color does not establish that the upstream power paths are independent. Eaton presents color coding as an identification aid for dual-source installations, not as proof of redundancy.
Release the order only when both endpoints, the complete assembly rating, and the equipment’s input requirements are known. Where a marking is unreadable or a datasheet omits a material condition, obtain the missing manufacturer documentation rather than filling the gap from appearance alone.