Lantronix SM24TBT2DPA User manual

SM24TBT2DPA
Managed Gigabit Ethernet PoE++ Switch
Install Guide
Part Number 33737
Revision L December 2022

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Intellectual Property
© 2021-2022 Lantronix, Inc. All rights reserved. No part of the contents of this publication may be transmitted or
reproduced in any form or by any means without the written permission of Lantronix.
Lantronix is a registered trademark of Lantronix, Inc. in the United States and other countries.
All other trademarks and trade names are the property of their respective holders.
Patented: https://www.lantronix.com/legal/patents/; additional patents pending.
Warranty
For details on the Lantronix warranty policy, go to http://www.lantronix.com/support/warranty.
Contacts
Lantronix Corporate Headquarters
48 Discovery, Suite 250
Irvine, CA 92618, USA
Toll Free: 800-526-8766
Phone: [phone]
Fax: [phone]
Technical Support
Phone: [phone] or 1.800.260.1312
Email: https://www.lantronix.com/technical-support/
Sales Offices
For a current list of our domestic and international sales offices, go to www.lantronix.com/about/contact.
Disclaimer
All information contained herein is provided “AS IS.” Lantronix undertakes no obligation to update the information
in this publication. Lantronix does not make, and specifically disclaims, all warranties of any kind (express, implied
or otherwise) regarding title, non-infringement, fitness, quality, accuracy, completeness, usefulness, suitability or
performance of the information provided herein. Lantronix shall have no liability whatsoever to any user for any
damages, losses and causes of action (whether in contract or in tort or otherwise) in connection with the user’s
access or usage of any of the information or content contained herein. The information and specifications
contained in this document are subject to change without notice.
Revision History
Rev
Date
Description of Changes
H
5/11/21
Update certifications and add power supply specs.
J 6/21/21
FW vB6.64.0031: add note on the time it takes for PoE++ power on the ports to power PDs
again after a cold restart. Add PoE force mode, support one VLAN interface gateway for
default route, add two icons (Mini fridge and Shade) to identify DMS devices.
K
7/28/21
Update Safety certification from EN60950 / IEC60950 to IEC62368-1/EN62368-1.
L 12/1/22
FW vB6.64.0079: add DHCP per port function to select a particular IP interface. Add two DMS device
icons. Change default settings: SNMP mode Disabled as factory default and change Auth Method
Configuration default. Add First Time Wizard. Add DHCP option 229 support. In PoE schedule, if Start
Time = End Time, reset PoE power on the ports. Update DMS Map View info. Add ConsoleFlow in
web/cli/api, add CF on-premise support, add CF S/N and LPM MAC address, and support API in https.
Note that SM24TBT2DPA is EoL. Note change to Power Supply monitoring.

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Contents
1Introduction ............................................................................................................................................4
Product Description ..................................................................................................................................................4
About This Manual ...................................................................................................................................................4
Related Documentation............................................................................................................................................4
Ordering Information ................................................................................................................................................4
Features ...................................................................................................................................................................5
PoE Features ...........................................................................................................................................................5
Benefits.....................................................................................................................................................................5
Specifications ...........................................................................................................................................................6
Software Features ....................................................................................................................................................8
Front Panel.............................................................................................................................................................11
LED Descriptions............................................................................................................................................... 12
Mode/Reset Button............................................................................................................................................ 14
Back Panel .............................................................................................................................................................14
Regional Versions of Power Cords ........................................................................................................................14
2Installation ............................................................................................................................................15
Package Contents ..................................................................................................................................................15
Safety Instructions for Rack Mount Installations ....................................................................................................15
Mounting the Switch in a 19-inch Rack ..................................................................................................................16
Mounting the Switch on a Desk or Shelf ................................................................................................................16
Installing SFP Modules...........................................................................................................................................17
Grounding...............................................................................................................................................................17
PS-AC-920 Power Supply Specifications...............................................................................................................18
Unpacking / Installing / Replacing Power Supplies ................................................................................................20
Unpacking Power Supply .................................................................................................................................. 20
Installing a Power Supply .................................................................................................................................. 21
Replacing a Power Supply ................................................................................................................................ 22
Connecting the AC Power Cord .............................................................................................................................22
Power Disconnection..............................................................................................................................................22
PoE vs. PoE+ vs. PoE++ .......................................................................................................................................23
PoE/PoE+/PoE++ Comparison ......................................................................................................................... 23
3Initial Switch Configuration ..................................................................................................................24
Initial Switch Configuration via Web Browser.........................................................................................................24
Initial Switch Configuration via CLI.........................................................................................................................25
4Troubleshooting ...................................................................................................................................26
Basic Troubleshooting............................................................................................................................................26
LED Summary ........................................................................................................................................................26
LED Troubleshooting..............................................................................................................................................27
Troubleshooting PoE Problems .............................................................................................................................28
PoE Modes and Compliance..................................................................................................................................29
Device Label and Box Label ..................................................................................................................................31
Record Device and System Information.................................................................................................................32
5 Regulatory and Safety Information.................................................................................................................33
Compliance and Safety Statements.......................................................................................................................33
High Risk Activities Disclaimer...............................................................................................................................33
Declaration of Conformity.......................................................................................................................................34
Record Device and System Information.................................................................................................................35
Cautions and Warnings ..........................................................................................................................................36
Electrical Safety Warnings .....................................................................................................................................37

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1 Introduction
Product Description
The SM24TBTDPA switch is a high performance Layer 2 managed switch with 52 Gbps switching capacity.
It provides (24) 10/100/1000 copper ports with IEEE 802.3bt PoE ++ capability and (2) additional 100/1000 dual
speed SFP/RJ-45 Combo ports. The SM24TBTDPA complies with the latest IEEE 802.3bt PoE++ standard and
supplies up to 90 Watts per port. It can provide up to 1640 Watts PoE output when equipped with the dual hot-
swappable power supplies. The embedded DMS (Device Management System) is designed to make it easy to use,
install and manage IP Phones, IP Cameras, high power WAPs, or LED lightening for enterprise applications.
The SM24TBT2DPA provides (24) 10/100/1000Base-T + (2) 100/1000Base-X SFP/RJ-45 Combo ports and one RJ45
Console port and includes (1) AC power supply and 19” rack mount brackets.
About This Manual
This manual describes how to install, initially configure, and troubleshoot the SM24TBT2DPA Switch, including:
•Install the switch
•Check switch status by reading the LED behavior
•Reset the switch or to restore the switch to factory defaults
•Use a Web browser or the CLI to initially configure the switch
•Troubleshoot the switch
Related Documentation
•SM24TBT2DPA Quick Start Guide, 33736
•SM24TBT2DPA Web User Guide, 33738
•SM24TBT2DPA CLI Reference, 33739
•SM24TBT2DPA API User Guide, 33822
•Release Notes (version specific)
Ordering Information
SKU
Description
SM24TBT2DPA
24-port Gigabit PoE++, 2-port SFP/RJ-45 Combo Managed Switch. Includes one AC
power supply (820 Watts) and 19” rack mount brackets.
SM24TBT2DPA-2XPS
24-port Gigabit PoE++, 2-port SFP/RJ-45 Combo Managed Switch. Includes two AC
power supply (820 Watts) and 19” rack mount brackets.
PS-AC-920
Secondary AC Power Supply (920 Watts); Optional; sold separately.
SFPs
Optional SFP modules sold separately. See our Optical Devices webpage.

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Features
Hot-swappable dual power supply modules
Support IPV4/IPV6 dual protocol stack
Support Jumbo Frame up to 9K bytes
Authentication – RADIUS, TACACS+
Security - Support SSH v1/SSH v2/SSL
Port based or tagged (802.1Q) VLAN, MAC based, Management VLAN and Private VLAN Edge
DHCP Relay, DHCP Server
L2/L3/L4 ACLs support MAC ACL, IP standard/extended ACL
LLDP (Link Layer Discovery Protocol)
IEEE 802.3az Energy Efficiency
IP Source Guard, Port Security
Management: Web management, SNMP V1/V2c/V3, Telnet, CLI
Quality of Service: Supports 8 hardware queues. Strict priority and WRR
Spanning Tree: Supports IEEE 802.1s MSTP, IEEE 802.1w RSTP and IEEE 802.1D STP Compliant
Rapid Ring
PoE Features
•Compliant with IEEE 802.3bt PoE++
•Compliant with IEEE 802.3at PoE+
•Compliant with IEEE 802.3af PoE
•802.1AB LLDP-MED Configuration
•PoE Configuration
•PoE Scheduling
•Auto Power Reset
•DHCP per Port
•Always on PoE
Benefits
Feature-rich Ethernet Switch for Enterprise-class: The switch delivers advanced functionality in a L2+
managed switch including Layer 3 static route, DHCP server, Ipv6 support, LLDP, etc. It also has
comprehensive security features such as IP source guard and ACL to guard your network from
unauthorized access. It builds on its market-leading price/performance with L2+ Managed GbE PoE switch,
to provide secure, reliable, simple enterprise or SMB deployments.
Easy to Install, Configure and Troubleshoot by DMS: The Device Management System provides embedded
functions to facilitate device management anytime and anywhere. Its user-friendly interface helps you
manage devices intuitively. It supports various IP device types (e.g., IP-phone, IP-camera, WAP) to enhance
manageability and save time and money during installation and maintenance stages.
Lower TCO with Energy-efficient Design: EEE is designed to help customers reduce power consumption
and lower the TCO with Energy Efficient Ethernet (IEEE 802.3az) features for building a green Ethernet
network environment.
Power over Ethernet Design: PoE++ extends the IEEE PoE+ standard to double the power per port to 60
watts. It has options to power IP devices with features like Always-On PoE, Power scheduling, Power delay,
PoE Auto Power Reset, and PoE configuration.

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Specifications
Port Configuration
Total Ports
RJ45 (10M/100M/1G)
Uplinks (100M/1G)
Console
26
24
2 RJ45/SFP Combo
1 RJ45
Hardware Performance
Forwarding Capacity
Switching Capacity
Mac Table
Jumbo Frames
38.68 Mbps
52 Gbps
8 K
9216 Bytes
Environmental Range
Operating Temperature
Storage Temperature
Altitude
Fahrenheit
Centigrade
Fahrenheit
Centigrade
Feet
Meters
+32° to +104°
0° to 40°
-4° to +158°
-20° to +70°
< 10000
< 3000
Dimensions, Weight, Humidity
Dimensions (W x D x H) Weight
Operating Humidity
Millimeters Inches Kilograms Pounds
442 x 300 x 44 17.4 x 11.8 x 1.73 4.75 10.47
10% to 90% non-
condensing
Voltage and Frequency
AC Input Voltage and Frequency
Voltage
100-240 VAC
Frequency
50~60 Hz
Output Power
Voltage
•54VDC/820W per Module
•Power Redundancy, Dual Hot Swappable Power Supplies
Power Consumption
Maximum Power Consumption without PoE:
•79 Watts with dual AC power modules
•52 Watts with single AC power module

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Power over Ethernet
Power Supplies Available PoE Power
With two Power
Supplies
Max 90 Watts output per port. Max PoE Budget 1640 Watts.
60 Watts for (24) ports simultaneously
90 Watts for (18) ports simultaneously
With one Power Supply
Max PoE budget 820 Watts. See the Web User Guide for more information.
30 Watts for (24) ports simultaneously
60 Watts for (13) ports simultaneously
90 Watts for (9) ports simultaneously
PoE Capacity
Available PoE Power Number of Ports that Support PoE (15.4W), PoE+ (30.0W), and PoE++ (60~90W)
820W with one Power
Supply
Each of Port 1-24 supports PoE, PoE+, PoE++ within available Power:
One Power Supply: 820W PoE Power with one 920W Power Supply module.
1640W with two Power
Supplies
Two Power Supplies: 1640W PoE Power with two 920W Power Supply modules.
See the Web User Guide for more information.
Standards
Standards
IEEE
802.3, 802.3u, 802.3z, 802.3ae, 802.3x, 802.3ad, 802.1D, 802.1w, 802.1s, 802.1Q,
802.1p, 802.1ad, 802.1AB, 802.3af, 802.3at, 802.3bt
Compliance
Regulation Regulatory Agency
Electromagnetic Emissions
(EMC)
FCC Part 15 Class A.
European Emission Standard EN55022/EN61000-3
Generic European Immunity Standard
European health, safety,
environmental protection
CE Marking
Safety IEC62368-1, IEC 60417-6172 (2012-09), UL.
MTBF
MTBF Environment
182,061 Hrs. GB, GC - Ground Benign, Controlled 25.00°C
99,282 Hrs. GB, GC - Ground Benign, Controlled 40.00°C

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Software Features
Layer 2 Switching
Spanning Tree
Protocol (STP)

Standard Spanning Tree 802.1d
Rapid Spanning Tree (RSTP) 802.1w

Multiple Spanning Tree (MSTP) 802.1s
Trunking
Link Aggregation Control Protocol (LACP) IEEE 802.3ad
Up to 13 groups

Up to 16 ports per group
VLAN
Supports up to 4K VLANs simultaneously (out of 4096 VLAN IDs)
Port-based VLAN
802.1Q tag-based VLAN
MAC-based VLAN
Management VLAN
Private VLAN Edge (PVE)
Q-in-Q (double tag) VLAN
Voice VLAN

GARP VLAN Registration Protocol (GVRP)
DHCP Relay 
Relay of DHCP traffic to DHCP server in different VLAN.

Works with DHCP Option 82
IGMP v1/v2/v3
Snooping
IGMP limits bandwidth-intensive multicast traffic to only the requesters. Supports
1024 multicast groups.
IGMP Querier IGMP querier is used to support a Layer 2 multicast domain of snooping switches in
the absence of a multicast router.
IGMP Proxy
IGMP snooping with proxy reporting or report suppression actively filters IGMP
packets in order to reduce load on the multicast router.
MLD v1/v2 Snooping Delivers Ipv6 multicast packets only to the required receivers.
Device Management System (DMS)
Graphical
Monitoring

Topology view: Support intuitive way to configure and manage switches and
devices with visual relations.
Floor view: It’s easy to drag and drop PoE devices and help you to build smart
workforces.
Map view: Enhance efficiency to drag and drop devices and monitor
surroundings on Google Maps.
Find my Switch
Search your real switches quickly and manage directly.
Traffic Monitoring
Displays a visual chart of network traffic of all devices to let you monitor every port at
any time from switches
Troubleshooting Network diagnostic, protection mechanism, performance and link management

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Layer 3 Switching
Ipv4 Static Routing Ipv4 Unicast: Static routing
Ipv6 Static Routing Ipv6 Unicast: Static routing
Security
Secure Shell (SSH)
SSH secures Telnet traffic in or out of the switch; SSH v1 and v2 are supported
Secure Sockets Layer
(SSL)
SSL encrypts the http traffic, allowing advanced secure access to the browser-based
management GUI in the switch
IEEE 802.1X
IEEE802.1X: RADIUS authentication, authorization and accounting, MD5 hash,
guest VLAN, single/multiple host mode and single/multiple sessions
Supports IGMP-RADIUS based 802.1X
Dynamic VLAN assignment
Layer 2 Isolation
Private VLAN Edge
PVE (also known as protected ports) provides L2 isolation between clients in the same
VLAN. Supports multiple uplinks
Port Security
Locks MAC addresses to ports, and limits the number of learned MAC address
IP Source Guard Prevents illegal IP address from accessing to specific port in the switch
RADIUS/ TACACS+ Supports RADIUS and TACACS+ authentication. Switch as a client.
Storm Control
Prevents traffic on a LAN from being disrupted by a broadcast, multicast, or unicast
storm on a port
DHCP Snooping A feature acts as a firewall between untrusted hosts and trusted DHCP servers
ACLs
Supports up to 256 entries. Drop or rate limitation based on:
•Source and destination MAC, VLAN ID or IP address, protocol, port,
•Differentiated services code point (DSCP) / IP precedence
•TCP/ UDP source and destination ports
•802.1p priority
•Ethernet type
•Internet Control Message Protocol (ICMP) packets
•TCP flag
Quality of Service (QoS)
Hardware Queue
Supports 8 hardware queues
Scheduling 
Strict priority and weighted round-robin (WRR)

Queue assignment based on DSCP and class of service
Classification

Port based
802.1p VLAN priority based
Ipv4/Ipv6 precedence / DSCP based
Differentiated Services (DiffServ)

Classification and re-marking ACLs
Rate Limiting

Ingress policer

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
Egress shaping and rate control

Per port
Management
DHCP Server
Support DHCP server to assign IP to DHCP clients
DHCP per Port
You can assign an IP address based on the switch port the device is connected to.
This will speed up installations of IP cameras; cameras can be configured after they
are on the network. The per-port assignment allows you to know which IP was
assigned to which camera.
Link-Local Address
binding interface
Configure Link-Local IP address to a different VLAN interface. The first IP interface
entry (169.254.xx.xx) is for the default value (VLAN 1). A link-local address is a unicast
address having link-only scope that can be used to reach neighbors. All interfaces on
routers must have a link-local address. Also, ADDRCONF requires that interfaces on
hosts have a link-local address.
Event Notifications
•Event Notification via Syslog and/or SNMP Traps
•Event Notification with 8 Severity levels
Remote Monitoring
(RMON)
Embedded RMON agent supports RMON groups 1,2,3,9 (history, statistics, alarms,
and events) for enhanced traffic management, monitoring and analysis
Port Mirroring
Traffic on a port can be mirrored to another port for analysis with a network analyzer
or RMON probe. Up to n-1 (where nis the max number of Switch Ports) ports can be
mirrored to single destination port. A single session is supported.
UPnP
The Universal Plug and Play Forum was formed to standardize discovery and control
of networked devices. See the Open Connectivity Foundation webpage.
s-Flow
The industry standard for monitoring high speed switched networks. It gives complete
visibility into the use of networks enabling performance optimization,
accounting/billing for usage, and defense against security threats
IEEE 802.1ab (LLDP)

Used by network devices for advertising their identities, capabilities, and
neighbors on an IEEE 802ab local area network

Support LLDP-MED extensions
Web GUI Interface
Built-in switch configuration utility for browser-based device configuration
CLI
For configuring / managing switch in Command Line Interface modes
Dual Image
Independent primary and secondary images for backup while upgrading
SNMP
SNMP version1, 2c and 3 with support for traps, and SNMP version 3 user-based
security model (USM)
Firmware Upgrade Web browser upgrade (HTTP/ HTTPs) and TFTP
Upgrade via the console port
NTP Network Time Protocol (NTP) is a networking protocol for clock synchronization
between computer systems over packet-switched

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Other Management

HTTP/HTTPs; SSH
DHCP Client/ DHCPv6 Client
Cable Diagnostics
Ping
Syslog
Telnet Client

IPv6 Management
Power over Ethernet (PoE)
Port Configuration Supports per-port PoE configuration function
PoE Scheduling
Supports per port PoE scheduling to turn on/off the PoE devices (PDs)
Auto Power Reset Checks the link status of PDs and reboots PDs if there are no responses
Power Delay
The switch provides power to the PDs based on configurable delay time when PoE
switch boots up, in order to protect switch from misuse of the PDs
Always on PoE
Lets you restart device, upload software, or swap active and alternate (backup)
firmware images while retaining PoE power to PDs. Note: It will take 75 - 80 seconds
to have PoE++ power on the ports to power PDs again if the switch makes a cold
restart. "Always on PoE" has no effect on this time.
Front Panel
The SM24TBT2DPA front panel LEDs, ports and buttons are shown and described below.

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LED Descriptions
The LEDs on the front panel provide switch status checking and monitoring. The three types of LEDs are described
below:
SYS (System) LED: indicates if the switch is powered up correctly or indicates if there is a system alarm triggered
for troubleshooting.
LED
Color
State
Description
System
Green
On
The switch is powered ON correctly.
Off
The switch is not receiving power.
Red On An abnormal state, such as exceeding operating temperature
range, has been detected in the switch.
Mode LEDs: indicate the mode of all RJ45/SFP ports on the switch. You can press the Mode button sequentially
to switch between the two different modes (Link/Activity/Speed mode and PoE mode).
LED
Color
State
Description
Link/Act/Speed Green On The Port Status LEDs display link status, network activity and
speed of each port.
PoE Green On The RJ45 Port Status LEDs display PoE powering status of each
port.
Power Supply LEDs: The LEDs on the Power Supply indicate Power Supply status.
LED
Color
State
Description
DC OK
Green
Red
--
On
On
Off
DC output is ready.
DC output has failed.
DC output is off.
AC OK
Green
Red
--
On
On
Off
AC output is ready.
AC output has failed.
AC output is off.

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Port Status LEDs: indicate the current status of each RJ45/SFP port. You can check these LEDs to understand the
port status in different modes, after changing the mode by pressing the Mode button.
Press the MODE button for less than 2 seconds to change LED modes (Link/Act/Speed Mode or PoE Mode); you
can then check the port status by reading the LED behaviors per the table below.
Table 3: Port Status LEDs
When Link/Act/Speed Mode LED Lit
LED
Color
State
Description
RJ45
Ports
Green On
The port is enabled and established a link to connected device, and the connection
speed is 1000Mbps.
Green Blinking The port is transmitting/receiving packets, and the connection speed is 1000Mbps.
Amber On
The port is enabled and established a link to connected device, and the connection
speed is 10/100Mbps.
Amber Blinking
The port is transmitting/receiving packets, and the connection speed is
10/100Mbps.
-- Off
The port has no active network cable connected, or it is not established a link to
connected device. Otherwise, the port may have been disabled through the switch
user interface.
SFP
Ports
Green On
The port is enabled and established a link to connected device, and the connection
speed is 1000Mbps.
Green Blinking The port is transmitting/receiving packets, and the connection speed is 1000Mbps.
Amber On
The port is enabled and established a link to connected device, and the connection
speed is 100Mbps.
Amber Blinking The port is transmitting/receiving packets, and the connection speed is 100Mbps.
-- Off
The port has no active network cable connected, or it is not established a link to
connected device. Otherwise, the port may have been disabled through the switch
user interface.
When PoE Mode LED Lit
LED
Color
State
Description
RJ45
Ports
Green On The port is enabled and supplying power to connected device.
Amber On An abnormal state, such as overload status, has been detected in the switch.
-- Off
The port has no active network cable connected, or it is not connected a PoE PD
device. Otherwise, the port may have been disabled through the switch user
interface.

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Mode/Reset Button
Pressing the front panel Mode/Reset button for a period of time lets you
perform these tasks:
•Change Port Status LED Mode: to read the port status correctly in the two
different modes (Link/Act/Speed mode or PoE mode).
•Reset the Switch: to reboot and get the switch back to the previous
configuration settings saved. Note that there is also a Non-Stop PoE (soft
reboot) feature allows the switch to reboot without affecting PoE port
power via the Web UI or CLI.
•Restore the Switch to Factory Defaults: to restore the original factory default settings back to the switch.
Note: Use the table below to determine which task is being performed by reading the LED behaviors while
pressing and holding the Mode/Reset button. When the LED behavior displays correctly, release the button.
Table 4: Mode/Reset Button Descriptions
Task to Perform Press Button for SYS LED Behavior Port Status LED Behavior
Change LED Mode 0 ~ 2 seconds ON Green LED status will change based on the mode
selected.
Reset the Switch 2 ~ 7 seconds Blinking Green ALL LEDs Off.
Restore to Defaults 7 ~ 12 seconds Blinking Green ALL LEDs stay On.
Back Panel
The back panel provides for dual hot-swappable 1560W power supplies for powering the switch. The switch ships
with one power supply (820 Watts) standard; order the secondary power supply module for the maximum power
(1640 Watts).
Regional Versions of Power Cords
These regional versions of the power cords and power supplies are available: -NA = North America, -LA = Latin
America, -EU = Europe, -UK = United Kingdom, -SA = South Africa, -JP = Japan, -OZ = Australia, and -BR = Brazil.

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2 Installation
Package Contents
Check the package contents to make sure you have received the following items. Contact your sales
representative if any item is damaged or missing. Please save the packaging for possible future use.
•One SM24TBT2DPA Switch with one AC Power Supply Module
•One Support Postcard (33504)
•One printed Quick Start Guide (33736)
•One DB9F to RJ45 Cable (6WPDB92RJ453)
•Four Rubber Feet (6RR2005AB4B2)
•Two Brackets (6EFS226C0E09)
•Eight Screws (6PF+UN3X5000)
Note: The switch is an indoor device. If it is to be used with outdoor devices such as outdoor IP cameras or
outdoor WAPs, then it is strongly suggested you install a surge protector or surge suppressor in order to protect
the switch.
Safety Instructions for Rack Mount Installations
The instructions below (or similar) are intended for rackmount installation environments:
1. Elevated Operating Ambient: if installed in a closed or multi-unit rack assembly, the operating ambient
temperature of the rack environment may exceed room ambient. Install the equipment in an environment
compatible with the maximum ambient temperature (Tma) specified.
2. Reduced Air Flow: install the equipment in a rack so that the amount of air flow required for safe operation is
not compromised.
3. Mechanical Loading: Mount the equipment in the rack so that a hazardous condition does not occur due to
uneven mechanical loading (weight distribution/rack balance).
4. Circuit Overloading: consider the connection of the equipment to the supply circuit and the effect that
overloading of the circuits might have on overcurrent protection and supply wiring. Consider all equipment
nameplate ratings when addressing this concern.

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5. Reliable Earthing: maintain reliable earthing of rack-mounted equipment; pay particular attention to supply
connections other than direct connections to the branch circuit (e.g., use of power strips).
Mounting the Switch in a 19-inch Rack
1. Attach the mounting brackets to both sides of the chassis. Insert screws and tighten with a screwdriver to
secure the brackets.
2. Place the switch on a rack shelf in the rack. Push it in until the oval holes in the brackets align with the
mounting holes in the rack posts.
3. Attach the brackets to the posts. Insert screws and tighten them.
Mounting the Switch on a Desk or Shelf
1. Verify that the workbench is sturdy and reliably grounded.
2. Attach the four adhesive rubber feet to the bottom of the switch.

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Installing SFP Modules
You can install or remove a mini-GBIC SFP module from an SFP port without having to power off the switch.
Note: The SFP ports should use UL Listed Optional Transceiver product, Rated 3.3Vdc, Laser Class 1. See the SFP
manual for specific cautions, warnings, and instructions. See the Lantronix SFP webpage for our full range of
Optical Devices. See the FOA webpage for additional information. The Fiber Optic Association, Inc.is an
international non-profit educational association chartered to promote professionalism in fiber optics through
education, certification and standards.
During installation and maintenance, avoid direct exposure to laser beams. Specifically, do not look into laser
ports. Ensure that each SFP port at which laser beams are (or will be) present is occupied by an SFP that is locked
in position.
1. Position the SFP device at either installation slot, with the SFP label facing up (Port 25) or down (Port 26).
2. Carefully slide the SFP device into the slot, aligning it with the internal installation guides.
3. Press firmly to ensure that the SFP device is firmly seated against the internal mating connector.
4. Attach an appropriate cable into the SFP module port.
5. Attach the other end of the cable to the other device.
Note: Do not remove and replace the SFP modules more often than necessary; excessive SFP removing/replacing
can shorten the SFPs useful life.
Grounding
ATTENTION:
This case must be earth grounded.
No DC input may be earth grounded.
Use Isolated Power Supply.

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PS-AC-920 Power Supply Specifications
CAUTION! Hazardous Area: Do Not remove this cover. Trained service people
only. No serviceable components inside.
LEDs: DC OK and AC OK LEDs on front panel. See “Power Supply LEDs” on
page 13.
Dimensions (H x W x D): 1-9/16” x 2-13/16” x 8-9/16” (25.4 m x 50.8 mm x 203.2 mm)
Warranty: 5 years warranty for the PS-AC-920.
Power Supply Voltage and Frequency
AC Input Voltage and Frequency
Voltage
100-240 VAC
Frequency
50~60 Hz
Output Power
Voltage
•54VDC/820W per Module
•Power Redundancy, Dual Hot Swappable Power Supplies
Power Supply Efficiency
The power supply efficiency will be higher than 80Plus Silver 230VAC internal specification without fan loading.
Input voltage
20% of full load
50% of full load
100% of full load
230Vac internal
85%
89%
85%
The power supply efficiency must meet the efficiency requirement with fan as shown in the table below:
Efficiency Standard
20% load
50% load
100% load
With fan/115Vac
84%
87%
86%
With fan/230Vac
86%
90%
89%
Power Supply Input Current
Input current will be less than 13A (rms) at 115Vac and 60 Hz.
Input current will be less than 6.5A (rms) at 230Vac and 50 Hz.
The input fuse value should be less than 15 A.
Input Voltage
Vin Range
Maximum Input
Current
230Vac internal
180-264Vac
6.5A@920W
230Vac internal
90-136Vac
13A@920W

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Power Supply Electrical Specification
Output requirements: The power supply has +54.5V single output. The table below specifies its output
parameters.
Parameter
+54.5V Output
Voltage
+54.5VDC
Minimum Current
0A
Maximum Current
16.88A
Line Regulation
+/-1%
Load Regulation
+/-3%
Overshoot
3%
Undershoot
3%
Maximum continuous output power: Maximum continuous output power is not to exceed 920W.
Over-voltage protection (OVP) : The outputs should be over-voltage protected. The output should never exceed +60V on
the +54.5V output.
Minimum
Typical
Maximum
OVP
+57.3V
+58.65V
+60V
Over-current protection (OCP) : The outputs should be over-current protected. The output should never exceed
21.84A@920W on the +54.5V output.
Minimum
Typical
Maximum
920W OCP
18.56A
20.256A
+21.84A
Power Supply LED Indication: Each module shall provide two LED status indicators on the front panel.
AC OK
DC OK
LED location
Right side of front panel.
Left side of front panel.
Color=GREEN
AC on line.
DC is good.
Frequency
1Hz
1Hz
Color=RED
Loss AC. @1+1
DC is failing. @1+1
Frequency
1Hz
1Hz
Note: “@1+1” the mean is 1+1 redundant mode condition.
DC OK and AC OK LED indication location diagram

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Power Supply PS-AC-920 MTBF
Environment
MTBF
GB, GC - Ground Benign,
230Vac Input line, Full Load, 25°C (Amb.)
857,983 Hrs.
GB, GC - Ground Benign,
115Vac Input line, Full Load, 25°C (Amb.)
697,667 Hrs.
GB, GC - Ground Benign,
230Vac Input line, Full Load, 50°C (Amb.)
219,472 Hrs.
GB, GC - Ground Benign,
115Vac Input line, Full Load, 50°C (Amb)
174,188 Hrs.
Unpacking / Installing / Replacing Power Supplies
The switch ships with one power supply (820 Watts) standard; order the second Power Supply for an additional
820 Watts.
Note: The switch supports dual redundant power supplies, and they are hot-swappable. You can apply the AC
power cord to any AC receptacle of the switch. If only one power supply is installed, it can be installed in either
bay. The table below refers to the specification of the input/output voltage to the switch; use the following
information to order the AC power cord.
Unpacking Power Supply
The optional second power supply is packed separately, if ordered. Unpack the optional second power supply and
save the packaging for possible future use.