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Packaged Mini-2N and Mini-4N UPS/RMSTS Systems

 A) Packaged Mini-2N System

These systems are ideal for a user who needs a prepackaged complete and isolated combined UPS and STS 2N system to protect a group of single corded critical loads. Ideal if you don’t want to intrude into your already installed large 2N system on site or if you need protection for a smaller server room with some single cord loads. You can also use this as a standard packaged solution for all your data centers that have single corded loads. The 2N UPSs are 80KVA, 480V, 3ph, 3W + G In, 480V, 3ph, 3W + G Out and sit on each side of a lineup of 2 outer UPS Modules (and typically 10 min. batteries) and the inner enclosures that contain the step down (from 480 to 208/120) Input Sections A and B, the STS Section, and the Output Section. The line up from left to right is as follows:

UPS A - This is an 80KVA high efficiency UPS with typically 10 minute sealed batteries in enclosure, one system located on each side of the line up. The type and manufacturer is decided by the user.

Input Section A – This section has a transformer that takes the output of UPSA at 480V and steps it down to 208V/120V which is connected to a distribution panel above it with single phase circuit breakers connected in a balanced fashion between the phases that will feed up to 6-8 (the number to be decided at order time) x 50A RMSTSs that can be either 120V or 208V or a mix. User determines how many of each at the time of order. Connections to this section are via the bottom (through the raised floor from the UPS to this section). Cables to be provided by installing contractor.

 STS Section - This section contains 6 to 8 x 50A TwinSource DCC-II RMSTSs. User determines how many should be 208V, how many should be 120V, or if all should be one or the other. No future additions should be contemplated so the loads in operation are not disrupted.

 Output Section - This section contains the user terminals where the feeders to the racks are terminated and run through the raised floor to their respective racks.

 Input Section B - Same as Input Section A above except connected to UPS B.

 UPS B - Same as UPS A above.

 All enclosures are front access only. You would purchase this line up from your local UPS manufacturer’s representative who would purchase the UPSs from the UPS supplier represented and the middle sections from TwinSource, all presented to you as a complete package. Please note the pdf One-Line and Outline Drawings of these systems below. There is only one pdf for the outline because the Mini-4N is just 2 sets of Min-2N’s.

 Redundancy Aspect - The critical loads are protected if any of the devices on side A fail (UPS, Battery, Step Down Transformer, Input Panel, Panel CBs). In such an even the RMSTSs would immediately transfer to side B.

 Maintainability Aspect – Each side A or B can be shut down for complete routine maintenance or parts replacement access without load disruption.

 Battery Time Aspect – Typically these UPSs would come with 10 min batteries. At part load utilization the time may extend to as much as 15 - 20 minutes (refer to battery data on extended discharge time vs % loading). With the advent of static switches the net time may be doubled again once the RMSTSs transfer from UPS A upon its depletion to UPS B with fresh batteries. So you may have a potential 30-40 min back up time.

 B) Mini-4N System (2 sets of Mini-2N’s connected to the same dual cord loads)

 These systems are ideal for users who need a prepackaged complete and isolated combined UPS and STS 4N system to protect both cords of dual corded critical loads. Each cord is supported by a separate 2N. The description of the Mini-4N is exactly the same as one Mini-2N x 2 sets with UPS designations A, B, C, and D in a paired fashion (A & B + C & D). Each dual corded load gets a feed from Mini 2N 1 and another Mini-2N 2.

Super Ultra Redundancy Aspect - The critical loads are protected if any or all of the devices in 3 of 4 quadrants fail (UPS, Battery, Step Down Transformer, Input Panel, Panel CBs). In such an event the RMSTSs would immediately transfer to the undisturbed side. As long as one of 4 sources is Ok, all the dual corded loads are ok thus making this configuration the most redundant with the highest resulting availability. This very configuration but using multi-megawatt UPSs is currently in use at some of the world’s most critical Air Traffic Control Sites in Europe. This is an ideal electrical configuration for super critical dual corded loads.

 Maintainability Aspect – Each side of each Mini-2n can be shut down one at a time for complete routine maintenance or parts replacement without load disruption. In fact one entire mini-2N at a time can also be accessed.

 Battery Time Aspect – Discharge time would be in excess of double that of Mini-2N because the total connected load is still 80KVA but protected by 4 x 80KVA UPS batteries.

 One-Line and Outline drawings of both systems above are shown below for download:

Mini 2N Outline Drawing graphic pdf/Mini2N and 4N One-Line Diagrams graphic

Download Mini-2N-Outline-Drawing

Download Mini2N-and-4N-One-Line-Diagrams

[Photos of typical sites where rack-mounted static transfer switches are used due to criticality of their operations.]

rack-mount static switch application photo



rackmount static transfer switch photo

rackmounted static transfer switch application photo



rackmount automatic static transfer switch application photo

rack-mount automatic static transfer switch application photo



Stand alone static transfer switches photo

rack-mounted static transfer switches photo


TwinSource USA • 32333 Aurora Road • Solon, Ohio, 44139, USA • (216) 408-2888
Contact: Fred Tamjidi • ftamjidi@twinsource.net

All specifications subject to change at supplier discretion without advance notification.

Types of Rack-Mount Transfer SwitchesTypical Installation of RM Transfer SwitchesBenefits of Static Transfer Switches
Implementation of Rack Mount Static Automatic Transfer SwitchesOverview of Automatic Transfer Switches
Mini-2N & Mini-4N UPS/RMSTS Systems | Where to StartContact TwinSourceHome

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