Intelligent Rack PDUs Basic, Metered, Switched & Outlet Metered PDUs Compared
Choosing a rack PDU is no longer just about outlet count. Intelligent PDUs measure energy, control individual outlets, connect to your DCIM and help prevent downtime caused by overloaded circuits or unplugged cords.
This guide compares the five PDU categories in the Telenco UK range – basic, input metered, switched, outlet metered and outlet metered & switched – and explains the features that matter for high-density and AI racks. New to PDUs? Start with our guide What is a PDU?.
Five Types of Rack PDU
Each category adds a level of visibility or control. All intelligent models share the same network management controller, display and design features; the difference is where power is measured and whether outlets can be switched.
Which Level of Intelligence Do You Need?
Basic – reliable distribution with locking, colour-coded outlets and circuit breakers. No network connection.
Input metered – measures power and energy for the whole PDU and each circuit breaker, locally and over the network.
Switched – adds remote on/off control of every outlet, with power-on sequencing.
Outlet metered – measures power and energy at every individual outlet.
Outlet metered & switched – outlet-level metering and switching in one PDU.
Intelligent PDU Features Compared
All four intelligent categories include circuit breaker monitoring, PDU-level energy metering, the network management controller and local displays. Choose switched models for remote outlet control, and outlet metered models to see the load of each device.
| Feature | Input Metered | Switched | Outlet Metered | Outlet Metered & Switched |
|---|---|---|---|---|
| Circuit breaker load monitoring & alerts | ✓ | ✓ | ✓ | ✓ |
| PDU and input phase energy metering (V, A, VA, kWh, pf) | ✓ | ✓ | ✓ | ✓ |
| Remote on/off control of every outlet | – | ✓ | – | ✓ |
| Power-on sequencing to avoid inrush overload | – | ✓ | – | ✓ |
| Disable unused outlets | – | ✓ | – | ✓ |
| Outlet-level energy metering (kWh) | – | – | ✓ | ✓ |
| Billing-grade metering, ±1% (ISO/IEC 62053-21) | ✓ | ✓ | ✓ | ✓ |
| Network management controller & dual network ports | ✓ | ✓ | ✓ | ✓ |
| Local displays with phase, breaker and alarm icons | ✓ | ✓ | ✓ | ✓ |
The terms smart, intelligent and managed PDU vary between manufacturers. Always check the features listed in each product specification.
Basic PDUs: 19" Rack Mounted and Vertical 0U
A basic PDU is a cost-effective choice where intelligence is not required, but it still offers advanced hardware such as colour-coded locking IEC outlets and circuit breakers. Basic PDUs suit lower-density racks, limited maintenance operations and installations where budget is a priority.
19" Rack Mounted (1U)
Universal and easily installed in any standard 19" rack. Front or rear mounting improves accessibility compared with 0U PDUs, and rear-mounted breakers reduce the risk of accidental disconnection.
Specs: 1 or 3 phases up to 63A · up to 12 C13/C19 outlets · 1U low depth up to 16A/32A · power cord 1m, 2m or 3m · IEC 60309 363P6 (IP44) or 363P6W (IP67) input.
Vertical 0U
Installed in the 0U space between the rack side panels and 19" profiles, or behind the profiles, so no rack units are used. Ideal for high-density racks where power needs are stable and remote monitoring is not required.
Specs: 1 or 3 phases up to 63A · up to 48 outlets, standard or combo 2-in-1 (C13/C15) and 4-in-1 (C13/C15/C19/C21) · power cord 1m, 2m or 3m · IEC 60309 363P6 (IP44) or 363P6W (IP67) input.
Chassis are available in black as standard, with blue, red, green, yellow, orange and white options.
Features That Reduce Downtime
Built for High-Density and AI Racks
High amperage: 125A/100A PDUs with locking outlets, including horizontal 19" PDUs for AI.
Combo and locking combo outlets: 2-in-1 C13/C15 and 4-in-1 C13/C15/C19/C21 outlets give high density with one PDU for mixed equipment.
Secure locking outlets: stop power cords coming unplugged through human error or vibration.
Colour coding: outlets coloured by circuit breaker, a full chassis colour range and user-defined electronic colour coding make power feeds easy to identify.
Toolless hot-swap NMC: replace or upgrade the network controller without powering down connected equipment.
DC power sharing: two-way power sharing keeps network management and alarms always on.
Network Management, Security & DCIM
Connectivity
Dual network ports (Gigabit and 10/100 Ethernet) with redundant Ethernet for each PDU. Supports SNMP, HTTPS, SSH, JSON, Redfish API and more for integration with your DCIM.
Daisy-chain
IP cascading manages up to 64 PDUs and 512 sensors through a single Ethernet connection and IP address.
Security
UL 2900-1 certified. Strong encryption, passwords and advanced authorisation including LDAP/S and Active Directory, with outlet-level user roles on switched models.
Monitoring
Data logging for capacity planning, user-defined alarm thresholds and notifications, and plug-and-play support for up to 10 digital environmental and access control sensors.
Planning PDUs for Redundant Power
Many server racks use two vertical PDUs fed from separate A and B supplies, so dual-corded equipment stays powered if one feed fails.
Circuit breaker monitoring measures loads across redundant feeds to help avoid overloading a breaker if one feed has to carry the full load.
Use different chassis colours or electronic colour coding for each feed so engineers can identify the power source at a glance and reduce human error.
Pair your PDUs with rack PDUs, server racks and cable management from Telenco UK.
PDUs Available from Telenco UK
A selection from our Rack PDUs range. Contact us for other configurations, input plugs, cord lengths and chassis colours.
0U PDU – 3 Phase – 32A – 42-Way – Managed
Three-phase intelligent PDU with 21 x C13/C15 and 21 x C13/C15/C19/C21 combo outlets, IP-based monitoring and individual outlet control.
0U PDU – 1 Phase – 32A – 40-Way – Metered
Single-phase PDU metered at input, with 20 x C13/C15 and 20 x C13/C15/C19/C21 outlets and an IEC 60309 32A input for up to 7.4kW.
0U PDU – 1 Phase – 32A – 30-Way – Basic
Basic vertical PDU with 24 x C13 and 6 x C19 outlets and an IEC 60309 32A input for straightforward power distribution.
How to Choose an Intelligent PDU
- Confirm the supply. Phase, current rating (16A to 63A, or 100A/125A for AI racks) and input plug.
- Count the outlets. Combo outlets let one PDU serve C13/C14 and C19/C20 equipment.
- Decide what to measure. Input metering for capacity planning; outlet metering for per-device loads or billing.
- Decide what to control. Choose switched models for remote reboot, sequencing and disabling unused outlets.
- Plan the network. Daisy-chain PDUs to save switch ports and IP addresses, and check DCIM protocol support.
- Plan redundancy. Use A and B feeds with different chassis colours.
Need help specifying PDUs for a data centre, colocation or AI project? Our team can recommend the right configuration.
Contact Our TeamIntelligent PDU FAQs
What is an intelligent PDU?
An intelligent (smart) PDU adds a network management controller to a rack PDU, so power can be measured, monitored and, on switched models, controlled remotely.
What is the difference between input metered and outlet metered PDUs?
An input metered PDU measures power for the whole PDU, each input phase and each circuit breaker. An outlet metered PDU also measures power and energy at every individual outlet, so you can see the load of each device.
What does a switched PDU do?
A switched PDU lets authorised users turn individual outlets on or off remotely, set power-on delays to sequence equipment, and disable unused outlets to prevent overload or unauthorised use.
What is a combo outlet?
A combo outlet accepts more than one connector type. 2-in-1 outlets take C14 and C16 plugs (C13/C15), while 4-in-1 outlets take C14, C16, C20 and C22 plugs (C13/C15/C19/C21).
What is PDU daisy-chaining?
Daisy-chaining (IP cascading) connects several PDUs through one Ethernet connection. Up to 64 PDUs and 512 sensors can be managed through a single IP address.
Why use coloured PDUs?
Coloured chassis and outlets make it easy to identify A and B power feeds and circuit breakers, reducing the risk of human error and unplanned downtime.
Do you supply high-amperage PDUs for AI racks?
Yes. The range includes high-amperage 125A/100A PDUs with locking outlets, including horizontal 19" PDUs for AI. Contact us with your requirements.
Find the Right Rack PDU
From basic 1U PDUs to outlet metered and switched intelligent PDUs, Telenco UK can help you power your racks reliably.
