Vertiv MP2-115HW 2U Hardwired Bypass Module for Liebert PSI5 UPS
Overview
The Vertiv MP2-115HW is a 2U rackmount Micropod bypass module designed specifically for Liebert PSI5-series UPS systems rated up to 1500VA running on 120V hardwired infrastructure. Where most facilities dread UPS maintenance windows — taking critical loads offline, scrambling for temporary power, or accepting avoidable risk — the MP2-115HW provides a dedicated bypass path so the upstream PSI5 can be serviced, swapped, or reconfigured while the connected load stays live. For IT closets, edge compute environments, and small data centers where a clean hardwired installation is already in place, this is a purpose-engineered solution rather than a workaround.
If you're running a PSI5 in a rack with hardwired branch circuits — no plug-and-socket intermediary — the MP2-115HW (often searched as MP2 115HW) is the companion bypass module that matches that wiring topology. Vertiv's broader Vertiv power protection catalog offers the full PSI5 family and the complete MP2 bypass module lineup for higher-amperage and NEMA-socket variants.
Key Features
- Hardwired input and output: Both the line-in and load-out connections are hardwired — no plug adapter, no derating from connector resistance, no loose NEMA plug to re-torque. This matters in permanently installed rack environments where a licensed electrician has already landed branch circuit wiring. You get a clean, code-compliant termination on both sides, which is the right approach for anything that's going to sit in a rack for years.
- Dedicated PSI5 bypass path: Maintaining a rackmount UPS typically means killing the load or running without protection during the service window. The MP2-115HW eliminates that tradeoff — it routes utility power directly to the load while the PSI5 is being serviced, meaning switches, servers, cameras, or NVRs downstream stay powered through the maintenance event.
- PSI5 compatibility up to 1500VA: The MP2-115HW is validated for all PSI5 models at the 1500VA tier and below. If you're running a PSI5-1500RT120 or any smaller PSI5 variant on a 120V hardwired circuit, this module is the correct bypass companion. It does not cover the PSI5-2200RT120 or PSI5-3000RT120 — those require a different MP2 variant.
- 2U rackmount form factor: Occupies 2U in a standard 19-inch rack — plan accordingly in dense deployments. Pair it with a rackmount power distribution layout review before installation if rack space is constrained.
- Reduces planned downtime risk: In environments like network closets supporting access control, IP camera NVRs, or VoIP infrastructure, even a brief power interruption during UPS maintenance can trigger device reboots, NVR recording gaps, or access control lockouts. The bypass module converts what would be a disruptive maintenance event into a transparent one.
- Simplified wiring architecture: The hardwired-in, hardwired-out design means no NEMA adapter chains in the signal path. For facilities with strict electrical code compliance requirements, this is a cleaner installation than adapter-based bypass solutions.
Integration and Compatibility
The MP2-115HW is engineered exclusively for the Liebert PSI5 UPS platform. It is compatible with all PSI5 models rated up to 1500VA on 120V circuits. If your deployment uses the PSI5-2200RT120 or PSI5-3000RT120, the correct bypass modules are the MP2-120HW and MP2-130HW respectively — both available in the Vertiv lineup. For facilities evaluating plug-in rather than hardwired bypass, the MP2-115A provides NEMA 5-15P input with eight 5-15R receptacle outputs for the same 1500VA PSI5 tier.
Consult your electrician and the PSI5 installation manual to confirm branch circuit sizing, conduit routing, and any local code requirements before terminating hardwired connections. This module sits between the incoming branch circuit and the PSI5, so wiring sequencing during installation is critical — the load should be on bypass before any work is done on the UPS itself.
For integrators building out camera and NVR rack assemblies where the PSI5 is providing runtime protection, the MP2-115HW is a professional-grade addition that signals to the end customer that the rack was designed for serviceability, not just initial deployment.
Frequently Asked Questions
Q: Which PSI5 UPS models is the MP2-115HW compatible with?
A: The MP2-115HW is compatible with all Liebert PSI5 models rated up to 1500VA operating on 120V circuits. It is not compatible with the PSI5-2200RT120 or PSI5-3000RT120 — those require the MP2-120HW and MP2-130HW respectively.
Q: What is the wiring configuration on the MP2-115HW?
A: Both the input and output connections on the MP2-115HW are hardwired — there are no NEMA plug or receptacle connectors. This is designed for permanent rack installations where branch circuits are landed directly to the module by a licensed electrician.
Q: Can the MP2-115HW be used with a PSI5-2200RT120?
A: No. The MP2-115HW is rated only for PSI5 models up to 1500VA. For the PSI5-2200RT120, use the MP2-120HW (hardwired) or MP2-120C/MP2-120E (plug-in variants).
Q: Is there a plug-in version of this bypass module for the same PSI5 1500VA tier?
A: Yes. The MP2-115A accepts a NEMA 5-15P input and provides eight NEMA 5-15R output receptacles, covering all PSI5 models up to 1500VA — the same UPS compatibility as the MP2-115HW but with a conventional plug-and-socket configuration.
Q: Does installing the MP2-115HW require powering down the connected load?
A: The purpose of the bypass module is to avoid powering down the connected load during UPS maintenance. The MP2-115HW provides a direct utility bypass path so the PSI5 can be serviced while the downstream equipment stays live. Consult the Vertiv installation documentation and follow proper lockout/tagout procedures during any electrical work.
The MP2-115HW is a straightforward but often-overlooked piece of infrastructure — a hardwired-in, hardwired-out bypass module that covers all Liebert PSI5 UPS models up to 1500VA on 120V circuits. In my experience, integrators who skip the bypass module on the initial build end up creating an avoidable service problem: the first time that UPS needs a battery swap or firmware update, someone is either taking the load down or accepting an unprotected interval. This module eliminates that decision entirely.
Technical Highlights:
- Hardwired I/O topology: No NEMA connectors in the bypass path means no connector-rated current derating and no plug maintenance. In a permanently installed rack, this is the correct architecture — both input and output land directly to branch circuit wiring.
- PSI5 coverage up to 1500VA: Validated for the full 1500VA and below PSI5 tier on 120V. If you're specifying bypass for a PSI5-2200RT120 or PSI5-3000RT120, you need the MP2-120HW or MP2-130HW respectively — the MP2-115HW will not fit those models.
- Model family context: Vertiv offers eight MP2 variants total. The MP2-115HW is the hardwired entry point of the lineup; the MP2-115A covers the same UPS tier with eight NEMA 5-15R receptacles if plug-in outputs are preferred at the load side.
Deployment Considerations:
- Wiring sequencing matters: the downstream load should be confirmed on bypass before any work begins on the PSI5 itself. Brief your installation team on the switchover procedure before the maintenance window, not during it.
- The hardwired configuration requires a licensed electrician for both installation and any future re-termination. If the facility does not have on-site electrical staff, factor that into your service planning — this is not a field-reconfigurable module the way a NEMA-plug version is.
The MP2-115HW is the right spec for network closets and edge rack deployments where a PSI5 at 1500VA or below is the primary UPS and the rack was designed with hardwired branch circuits from the start — think access control head-end closets, small NVR enclosures, or telecom-grade IDF rooms where serviceability was built into the design.
