Next Generation PoE Standards and Codes Update Frank Straka Panduit Corporation
Introduction Power over Ethernet is a HOT topic! New power levels dramatically increasing PoE device types New standards for equipment and cabling New code developed by NFPA for 2017 NEC New UL listing for PoE cables What do you need to know and what should you do?
Topics for Discussion Review the new PoE standard Discuss impact of PoE on cabling performance Discuss impact of NFPA codes on cabling Recommendation for putting it all together
What is PoE? Data and power over a single twisted pair cable Category 5e, 6, or 6A Terminology: Power Sourcing Equipment (PSE): A device that delivers (sources) power over a twistedpair copper cabling channel to a powered device. For example, a switch. Powered Device: (PD): A device that receives power from a PSE over the twisted-pair copper cabling channel. For example, an IP phone. Endspan: PSE type located at the end of the twisted-pair channel. For example, a switch. Midspan: PSE type located between a non-poe switch and a PD. Also called a PoE injector
How does PoE work? TODAY: IEEE802.3af, IEEE802.3at Type 1 & 2 Trade names of PoE, PoE+ Max speed of 1000BASE-T Power on 2 out of 4 pairs Up to 600mA / pair (300mA / wire) PSE: Max of 30W PD: Max of 25.5W PSE PD
Where is PoE Going? TOMORROW: IEEE802.3bt, Types 1, 2, 3, and 4 Trade names of PoE++, 4PPoE Max speed of 10GBASE-T Power on 4 out of 4 pairs Up to 960mA / pair (480mA / wire) PSE: Max of 99.9 W PD: Max of 71 W PSE PD
PoE Standards Summary Type Standards Maximum Current Number of Energized Pairs Power at Source Power at Device Maximum Data Rate Standard Ratified PoE IEEE 802.3af (802.3at Type 1) 350 ma 2 15.4 W 13 W 1000BASE-T 2003 PoE+ IEEE 802.3at Type 2 600 ma 2 30 W 25.5 W 1000BASE-T 2009 PoE++ (4PPoE) Proposed IEEE 802.3bt Type 3 Proposed IEEE 802.3bt Type 4 600 ma 960 ma 4 60 W 99 W 51 W 71 W 10GBASE-T Expected 1Q2018 No IEEE standard Cisco UPOE HDBaseT (www.hdbaset.org) 600 ma 1000 ma 4 60 W 100 W 51 W 100 W Varies Exists today no official ratification
Why is the new PoE standard exciting? TODAY TOMORROW
Summary of New PoE Standards Uses 4 out of 4 pairs Up to 71W to end devices Up to 10GBASE-T data rates Called PoE++ or 4PPoE
Topics for Discussion Review the new PoE standards Discuss impact of PoE on cabling performance Discuss impact of NFPA codes on cabling Recommendations for putting it all together
Cabling PoE Frequently Asked Questions What are the cabling requirements for PoE? For the new 4PPoE standard, 4-pair Category 5e or higher. Will the device get the power it needs regardless of cable length? YES. As long as the channel is standards compliant Cat 5e to Cat 6A at 100 meters or less, it will get the power it needs. Is there a difference between Categories? YES. PoE++ will run on Cat 5e and higher cabling. However, Category 6A provides the best thermals and power efficiency.
Standards Governing Cabling PoE IEEE P802.3bt Task Force Overall standard governing equipment and cabling TIA TSB-184-A Technical Service Bulletin on Guidelines for Supporting Power Delivery Over Balanced Twisted-Pair Cabling ISO/IEC TR-29125 and CENELEC TR 50174-99-1 International cabling guidelines for PoE++ ANSI/TIA-568-C.2 Familiar standard covering cabling performance IEC 60512-99-002 Standard for connectivity with engaging / disengaging PoE
TSB-184-A Overview Revision of old document to support higher power and current levels Tested multiple cable bundle sizes Measured temperature rise in center of bundle Limit temperature rise to less than 15 o C above ambient Temperature rise can: Cause signal degradation (e.g., attenuation) Cause long-term damage if temperature exceeds cable rating
Actual Results from TSB-184-A Testing 100-cable bundles Cat 6 and 6A, 28, 26, and 23 AWG performance with PoE Implications: All gauges work, have different bundle size limits All gauges will have different temp rises for different bundles sizes Cat 6A has best performance
Max Bundle Sizes for 15 o C Temp Rise 26 AWG Category 5e Category 6 Category 6A Category 8 Air Conduit Air Conduit Air Conduit Air Conduit Air Conduit 600mA 24 24 214 145 316 234 310 253 917 509 720mA 24 24 135 88 206 145 204 159 590 316 1000mA 24 16 56 33 92 58 93 65 257 127 From TIA TSB-184-A, Draft 6.1, Table A.5. Subject to change as document goes through ballot process (and subject to NEC 2017 compliance) Follow these guidelines to stay under 15 o C temperature rise Consult cable vendor for actual thermal rise in bundles Values shown here are conservative
ANSI/TIA-568-C.2 Overview Balanced Twisted-Pair Telecommunications Cabling and Components Standards Most people are familiar with this standard It is what you test channels and links to Provides guidance on effect of heat on cable insertion loss
Effect of Heat on Channel Length Temperature ( o C, ( o F)) Maximum* horizontal length, unscreened (m) Maximum* horizontal length, screened (m) 20 (68) 90.0 90.0 25 (77) 89.0 89.5 30 (86) 87.0 88.5 35 (95) 85.5 87.7 40 (104) 84.0 87.0 45 (113) 81.7 86.5 50 (122) 79.5 85.5 55 (131) 77.2 84.7 60 (140) 75.0 83.0 * Assumes 10 meters of patch at 20 degrees C From ANSI/TIA-568-C.2, Table G.2 Additional insertion loss at higher temperature de-rates maximum channel lengths Conservative values Use vendor headroom warranties to estimate performance Consult cable vendor for specific performance
Temperature Rise Per Bundle Size Bundle Size MODEL, Cat 5e, 600 ma MODEL, Cat 6A, 600 ma MEAS., Cat 6A, 600 ma MODEL, Cat 5e, 1000 ma MODEL, Cat 6A, 1000 ma MEAS., Cat 6A, 1000 ma 7 1.3 o C 0.8 o C 0.2 o C 3.7 o C 2.2 o C 1.4 o C 24 3.0 o C 1.9 o C 0.5 o C 8.2 o C 5.2 o C 3.4 o C 48 4.8 o C 3.2 o C 0.8 o C 13.3 o C 8.8 o C 5.7 o C 61 5.7 o C 3.8 o C 1.0 o C 15.8 o C 10.7 o C 6.8 o C 91 7.7 o C 5.3 o C 1.1 o C 21.3 o C 14.7 o C 8.9 o C 100 8.2 o C 5.7 o C 1.2 o C 22.9 o C 15.9 o C 9.2 o C Cat 6A has the least temperature rise Both measured and modeled What does that mean for you?
What is the Impact to You? Heat of cable governed by: Ambient temperature Type of PoE used Category cable type (and its implementation) Bundle size Insertion Loss affected by Heat Therefore, can a relationship be established between bundle size and channel length? For a given ambient temperature, and assuming 4PPoE type 4?
Putting it all Together 5m loss! Use the channel table to compute effect of temperature rise to channel length Model shows 7 o C improvement with Cat 6A over Cat 5e Cat 5e exceeds 15 o C limit 7 o C translates to a loss of ~3 meters Measured shows 13.7 o C improvement with Cat 6A over Cat 5e 13.7 o C translates to a loss of ~5 meters Recommendation: INSTALL CAT 6A!
Ways to Mitigate Heat Rise 91 cable bundle 3 bundles of 37, no separation 3 bundles of 37, 1 separation 14.7 o C heat rise 11.8 o C heat rise 8.2 o C heat rise 25% higher 30% lower Per draft 6.1 of TSB-184-A, assuming Cat 6A cables, 1000 ma on all 4 pairs
Cat 6A is more efficient Cat 5e = more heat = more power lost Cat 6A is more efficient Larger wires, less heat, more power transferred How efficient? Cable Type Power Lost Category 5e 24.4 W Category 6A 20.1W Category 6A is 4.3 W more efficient per link!
Summary of PoE Performance Standards Install Cat 6A Cat 6A has larger bundle sizes Cat 6A can go longer reaches with PoE Cat 6A is more efficient
Topics for Discussion Review the new PoE standards Discuss impact of PoE on cabling performance Discuss impact of NFPA codes on cabling Recommendations for putting it all together
Impact of 2017 NEC Code Generally does not apply for power supplied over a communications cable when power levels are 60 watts or less Applicable for PoE++, Type 4 Not applicable for PoE++, Type 3 60 W covers vast majority of installations Recognizes a new UL listing for Limited Power (LP) cables LP listed cables are NOT required to run PoE If you do not have LP listing, you have to watch bundle sizes per ampacity table Uncertainty on how inspection will work Likely will vary by state and local interpretations Speculation: Inspections may occur by application type
When will the 2017 NEC Apply to Me? Depends on state Some states do not have statewide adoption Some states 1 or 2 versions behind Code is always open to interpretation at a local/state level!
How to Apply the 2017 Code Type Standards Maximum Current Number of Energized Pairs Power at Source Power at Device PoE IEEE 802.3af (802.3at Type 1) 350 ma 2 15.4 W 13 W PoE+ IEEE 802.3at Type 2 600 ma 2 30 W 25.5 W PoE++ (4PPoE) Proposed IEEE 802.3bt Type 3 600 ma 4 60 W 51 W PoE++ (4PPoE) Proposed IEEE 802.3bt Type 4 960 ma 4 90 W 71.3 W NEC 2017 not a concern NEC 2017 imposes new requirements
If the NEC 2017 Requirements Apply You are running IEEE802.3bt Type 4 PoE++ Either: Use a LP listed cable rated to at least 0.5A OR Refer to ampacity table 725.144 for bundle size. Bundle size depends on: Cable Temperature Rating Wire Gauge Ambient temperature
LP Cables LP means Limited Power Example Marking: TYPE CMP-LP(0.5A) (UL) 23 AWG 90 o C New LP marking after CMP LP(0.5A) covers PoE++ Type 4 up to 100W 0.5A refers to amperes per wire Higher LP ratings such as 0.7A are up to 140W
Ampacity Table AWG Number of 4-Pair Cables in a Bundle 1 2-7 8-19 20-37 38-61 62-91 92-192 Temp Rating Temp Rating Temp Rating Temp Rating Temp Rating Temp Rating Temp Rating 60 o C 75 o C 90 o C 60 o C 75 o C 90 o C 60 o C 75 o C 90 o C 60 o C 75 o C 90 o C 60 o C 75 o C 90 o C 60 o C 75 o C 90 o C 60 o C 75 o C 90 o C 26 1.0 1.0 1.0 1.0 1.0 1.0 0.7 0.8 1.0 0.5 0.6 0.7 0.4 0.5 0.6 0.4 0.5 0.6 NA NA NA 24 2.0 2.0 2.0 1.0 1.4 1.6 0.8 1.0 1.1 0.6 0.7 0.9 0.5 0.6 0.7 0.4 0.5 0.6 0.3 0.4 0.5 23 2.5 2.5 2.5 1.2 1.5 1.7 0.8 1.1 1.2 0.6 0.8 0.9 0.5 0.7 0.8 0.5 0.7 0.8 0.4 0.5 0.6 22 3.0 3.0 3.0 1.4 1.8 2.1 1.0 1.2 1.4 0.7 0.9 1.1 0.6 0.8 0.9 0.6 0.7 0.8 0.5 0.6 0.7 Note 1: For bundle sizes over 192 cables, or for conductor sizes smaller than 26 AWG, ampacities shall be permitted to be determined by qualified personnel under engineering supervision. Note 2: Where only half of the conductors in each cable are carrying current, the values in the table shall be permitted to be increased by a factor of 1.4. For common 23AWG cables: Maximum bundle size for a 60 o C rated cable running 802.3bt Type 4 is 91 cables Maximum bundle size for a 75 o C or 90 o C cable running 802.3bt Type 4 is 192 cables
Summary of 2017 NEC Code Only applies for > 60W (Type 4) New UL listing for LP cables LP rating of at least 0.5A needed Without LP refer to ampacity table
Topics for Discussion Review the new PoE standards Discuss impact of PoE on cabling performance Discuss impact of NFPA codes on cabling Recommendations for putting it all together
How big to bundle? Now there are 2 documents discussing bundle sizes Performance (TSB-184-A) NEC ampacity table for non-lp cables How do you put them together?
What you need to know What is the ambient temperature? What is the length of the channel? Is the cable LP rated? If not, what is the cable temperature rating and wire gauge? What this determines: Maximum bundle size
Example: 92 meter channel needed, Setting: Want to run PoE++, type 4 Cable has 60 o C rating Ambient is 30 o C Cable is 23AWG Cable is Cat 6A Cable is NOT LP rated no LP cables NEC 2017 ampacity table limits to 91 cables Per ANSI/TIA-568-C.2 IL table: Channel derating of 8 meters occurs with a cable temperature of 45 o C 45 o C derating implies a 15 o C bundle temperature rise over ambient (30 o C + 15 o C) Per TSB-184-A, Cat 6A bundle model says cable can be >91 cables for 15 o C temp rise Per actual test data, Cat 6A bundle can be > 100 cables for 15 o C temp rise BUNDLE SIZE LIMIT: 91 cables per NEC 2017 ampacity table
Example: 92 meter channel needed, Setting: Want to run PoE++, type 4 Cable has 60 o C rating Ambient is 30 o C Cable is 23AWG Cable is Cat 6A Cable IS LP listed for 0.5A with LP cables LP cables allow you to not refer to ampacity table Per ANSI/TIA-568-C.2 IL table: Channel derating of 8 meters occurs with a cable temperature of 45 o C 45 o C derating implies a 15 o C bundle temperature rise over ambient (30 o C + 15 o C) Per TSB-184-A, Cat 6A bundle model says cable can be >91 cables for 15 o C temp rise Per actual test data, Cat 6A bundle can be > 100 cables for 15 o C temp rise BUNDLE SIZE LIMIT: Follow TSB-184-A or vendor guidance on bundle size limit
Example: 92 meter channel needed, Setting: Want to run PoE++, type 4 Cable has 75 o C rating Ambient is 30 o C Cable is 24AWG Cable is Cat 5e Cable IS LP listed with Cat 5e LP cables LP cables allow you to not refer to ampacity table Per ANSI/TIA-568-C.2 IL table: Channel derating of 8 meters occurs with a cable temperature of 45 o C 45 o C derating implies a 15 o C bundle temperature rise over ambient (30 o C + 15 o C) Per TSB-184-A, Cat 5e model says cable can be <61 cables for 15 o C temp rise BUNDLE SIZE LIMIT: Follow TSB-184-A for 61 cables Cat 5e has much worse performance. INSTALL CAT 6A!
Summary LP shifts bundle size to TSB-184-A Without LP, TSB-184-A & ampacity table Understand ambient, bundle temp Install Cat 6A for best performance
Questions?