Mirapath, Inc.

Benefits

Benefits of Power Management

It is SMART to have power management. It provides for business and operational efficiencies – saving money. Some benefits include:

1. No need for weekly walk troughs with power meters. Get real time and historical reports on power consumption KW/h per location, per row of racks, per cabinet, per power strip.
2. Get alerts when surpassing a certain power threshold on a particular feed. Prevent unnecessary downtime by preventing overloads in your circuit.
3. Have the ability to power cycle devices at your fingertips. Anytime, Anywhere. No waiting for a service tickets.
4. Identify comatose servers in your environment. Comatose servers are unused servers that are costing you power and taking up space in you infrastructure. Gartner says that by, “removing a single x86 server from a data center will result in savings of more than $400 a year in energy costs alone… business could reduce 5% to 20% of the overall server count”
5. Have better, more accurate tools for capacity planning. With power densities at a single rack increasing every year from 3KW in 2000 to almost 20KW in today’s infrastructure, power consumption and availability is major consideration in IT planning.
6. Keep your collocation honest. Are you being billed for the actual power you are using?
7. Compare current power consumption with historical data and benchmarks. Are your green initiatives paying off? EPA is awarding Energy Star rating to data centers that meet certain energy efficiency requirements. You cannot show improvement on your energy consumption without a base measurement of where you started.

Components

1. Power Management Software.  Visibility and access to power information is so critical that many enterprise companies have developed internal tools and software to have this information available to them.  In recent years, many power strip manufacturers have developed sophisticated software solutions to provide customers with visibility and control of their power strips at the cabinet level.

Considerations when selecting a power management software solution:

- Can it handle different manufacturer power strips?
- Does it provide for redundancy?
- What is the ease of importing power strip information?
- Security features? Does it integrate with LDAP, TACACS?
- What kind of report does it provide?
- Does it provide for mass configuration and mass updates?
- Does it tie in with my building management system?
- Does it tie in with my data center infrastructure management (DCIM) solution?

 

2. Cabinet Power Strips. Cabinet power strips go from dumb power strips with no LED to the fully IP addressable power strip with individual outlet metering and switching. They also go from 120 volts to 3 Phase to DC power strips to fail safe transfer switches.

 

Considerations when selecting a power strip:

• Type of power strips:

- basic
- metered with LED display
- metered with Ethernet
- switched
- with individual outlet monitoring and switching
- fail safe transfer switches
- 48VDC power strips

• Specifications

- form factor
- types of receptables
- types of output plug
- voltage
- amperage
- physical dimensions (How and where will be racked on the server cabinet?)

• Trade off analysis

- If just getting a power strip with NO LED, what is the price differential from a power strip with LED, to one that is IP based with switchable outlets? Would the benefits of a switched strip justify the cost difference? How much does remote hands costs? How much does 1 hour of downtime costs?

- Does it make sense to go 208V? Does it make sense to go 208V 3 phase? How many more servers can you connect with a 3 phase feed? How much does your colo charge for a 3 phase feed? Would there be any cost savings?

• How does it fit in with the rest of your infrastructure? Can I integrate my remote power management with my console server and KVM access?

3. Power Cords. These jumper cables are often overlooked. If ordered correctly, they are a non-issue.  If ordered incorrectly or without a proper fit, power cords can be messy in your rack, block airflow, delay installations, and potentially even cause unnecessary downtime.

Considerations when selecting power cords:

• What are they rated at? 250V? 10Amps, 15Amps?
• Will the mold fit your outlet well?
• Will it fit your retainer clip on the strip?
• Do the power cords come coiled or bunched?

Many of you already know the difference between a C13 and C14 or C19 and C20. But what is a C15? And, what are Y cables used for? To help decipher the power cord nomenclature, we put together a chart of the most commonly used power jumpers/cords so you have it handy. View this handy chart we've put together to help you identify each power cord.

Customer Success Story

Gaming company switches to 208V 30Amps 3phase power - Reducing number of drops per cabinet and generated savings of over 45%.

Challenge:

Customer is expanding to a new collocation facility. They are considering different power strips and ways to maximize power drops, densities, and rack space. In their past configuration, the customer used 208V 30Amps single phase power. Each rack has 4 feeds totaling 20 KW of usable power. Going forward, they want to

Solution:
Mirapath worked with the customer to calculate total available power based on different power input combinations, rack space use, costs of power drops and power strips, and number of servers supported.

Also, Mirapath provided competitive analysis of different power strip manufacturers and models of power strips.

Results:
Based on the calculations, the customer decided to switch from 4 x 208V 30Amps single phase per cabinet to 2 x 208V 30Amps 3 phase power in feeds. With the 2 x 208V 30Amps 3 phase power drops, the customer has 17KW which is less than the original 20KW. But it also achieved 45% in savings in the costs of power drops and power strips.  In this configuration, the customer will also have room to increase rack density by adding additional feeds to the rack.

Customer Success Story 2

A hosting company maximizes power feeds to support blade chassis.

Challenge:

To conserve energy costs, the customer is using 2 x APC AP7941 to connect 4 blade Dell chassis, running between 10-15 Amps each chassis. Assuming each chassis draws on average 12 Amps, the total consumption = 2,496 Watts per chassis for a total of 9,984 per rack for the 4 chassis.

But running at such full capacity and density is generating issues for the customer:

1.  No true redundancy as each feed is already fully loaded. Based on our assumption that each chassis is at 12 Amps, each feed is at 24Amps. If A feed fails and it fails over to B, it would overload B feed.

2. The APC AP7941 has 2 x 15 amp breakers in the units so the customers’ power strips overloads prematurely even if the whole strip load rating is below 24Amps.

Solution:

1. Switch to 208V 30Amps 3 phase with 2 x 208V 30Amps 3 phase feeds. The total watts available would be 21,590.

2. Increase to 4 feeds of 208V, 30Amps. The total watts available would be 24,960, which at 80% value can still provide a failover redundancy.

3. Switch to a power strip that can provide higher amperage rated breakers.

	Volts	Amps	Phase	Watts per circuit	Circuit per rack	Watts per rack
Current situation	208	30	1	6,240	2	12,480
208 3 phase option	208	30	3	10,808	2	21,615
208V single phase	208	30	1	6,240	4	24,960