Lantronix SM4T4DPA User manual

SM4T4DPA
Managed Layer 2 Gigabit Ethernet Switch
(4) 10/100/1000Base-T Ports + (4) 100/1000Base-X SFP Slots
Install Guide
Part Number 33867
Revision A August 2023

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Intellectual Property
© 2022, 2023 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
Online: 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
Date
Rev
Description
8/21/23
A
Initial Lantronix release at FW v 2.66.

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Contents
Revision History ........................................................................................................................................................2
Product Description ...................................................................................................................................................5
Ordering Information .................................................................................................................................................5
About this Manual......................................................................................................................................................5
Related Manuals .......................................................................................................................................................5
For More Information.................................................................................................................................................5
Features.................................................................................................................................................................5
Specifications.........................................................................................................................................................6
Cautions and Warnings .............................................................................................................................................7
Hardware Description................................................................................................................................................8
Switch Architecture ................................................................................................................................................8
Network Management Options ..............................................................................................................................8
Front Panel ............................................................................................................................................................8
Back Panel.............................................................................................................................................................8
1000BASE-T Ports ................................................................................................................................................9
SFP Transceiver Slots ...........................................................................................................................................9
Port and System Status LEDS ..............................................................................................................................9
AC Input .................................................................................................................................................................9
Network Planning.................................................................................................................................................10
Application Examples ..........................................................................................................................................10
Installation ...............................................................................................................................................................12
Equipment Checklist ............................................................................................................................................13
Package Contents ...............................................................................................................................................13
Mounting..................................................................................................................................................................13
Rack Mounting.....................................................................................................................................................13
Desktop or Shelf Mounting ..................................................................................................................................14
Installing an Optional SFP Transceiver ...............................................................................................................15
Connecting to a Power Source............................................................................................................................15
Connecting to the Console Port...........................................................................................................................16
Making Network Connections..................................................................................................................................18
Connecting Network Devices ..............................................................................................................................18
Troubleshooting.......................................................................................................................................................21
Basic Troubleshooting Tips..................................................................................................................................21
Troubleshooting Chart .........................................................................................................................................21
Cables .....................................................................................................................................................................23
Twisted-Pair Cable and Pin Assignments............................................................................................................23
10BASE-T/100BASE-TX Pin Assignments..........................................................................................................23
Specifications ..........................................................................................................................................................27
Physical Characteristics.......................................................................................................................................27

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Switching Features ..............................................................................................................................................27
Management Features.........................................................................................................................................27
Standards ............................................................................................................................................................27
Compliance..........................................................................................................................................................28
Regulatory Agency Information ...............................................................................................................................28
RoHS, WEEE, and Environmental Programs......................................................................................................28
Declaration of Conformity ....................................................................................................................................28

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Product Description
This switch is a high performance Layer 2 managed switch with (4) 10/100/1000Base-T copper ports and (4) dual
speed 100/1000Base-X SFP slots.
Ordering Information
SM4T4DPA
Managed Layer 2 Gigabit Ethernet Switch wit (4) 10/100/1000Base-T Ports + (4)
100/1000Base-X SFP Slots.
SFP Modules
See Lantronix full line of SFP transceivers on our SFP webpage.
RMSM4-01
19“ Rack Mount Bracket.
BRSM8-01
Wall Mount Bracket.
Power Cord
Included
To order the corresponding country specific power cord, add the appropriate extension
to the end of the SKU: -NA = North America, -LA = Latin America, -EU = Europe,
-UK = United Kingdom, -SA = South Africa, -JP = Japan, -OZ = Australia, or -BR = Brazil.
About this Manual
This guide gives specific information on how to install, set up, and troubleshoot the switch. The manual is intended
for use by network administrators who are responsible for installing and maintaining network equipment;
consequently, it assumes a basic working knowledge of general switch functions, the Internet Protocol (IP),
Ethernet switches and networking, and Simple Network Management Protocol (SNMP). Transition Networks is now
Lantronix. Some products/firmware items are still in process of being re-branded and may still reflect the Transition
Networks name/logo
Related Manuals
•SM4T4DPA Web User Guide, 33868
•SM4T4DPA CLI Reference, 33869
•Software Release Note (version specific)
For More Information
For Lantronix Documentation, Firmware, App Notes, etc. go to https://www.lantronix.com/technical-support/.
Note that this manual provides links to third party web sites for which Lantronix is not responsible.
Features
•Supports Jumbo Frame up to 9K bytes
•Authentication – RADIUS IEEE 802.1X, TACACS+
•Security - supports SSH/SSL
•Port based or tagged (IEEE 802.1Q) VLAN, QinQ double tag VLAN, Guest VLAN
•Bandwidth Allocation Ingress and Egress
•DHCP Snooping including option 82
•IP-MAC binding for security
•ACL based on Ethernet Type / ARP / IPv4 for packets permit or deny, rate limitation and port copy
•LLDP (Link Layer Discovery Protocol)
•Syslog for device management
•IEEE 802.3az Energy Efficiency
•Single IP management
•Web Management, SNMP V1/V2c/V3, Telnet, CLI
•Supports IEEE 802.3ad port trunk with link aggregation control protocol (LACP)

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•Supports IGMP Snooping V1/V2/V3, IGMP Proxy and GVRP
•Supports 8 hardware queues with Strict priority and WRR. Per port bandwidth management
•Supports IEEE 802.1s MSTP, IEEE 802.1w RSTP and IEEE 802.1D STP Compliant
•Port Based VLAN, IEEE 802.1Q tag-based, 4096 VLAN entries, MACbased VLAN, Private VLAN Edge,
Priority VLAN override
•Firmware Update, configure backup/restore through Web GUI and TFTP
•Support IPv4/IPv6 dual protocol stack
•Redundant Ring Protection Protocol
Specifications
Standards: IEEE 802.3, IEEE 802.3u, IEEE 802.3z, IEEE 802.3x, IEEE 802.3ad, IEEE 802.1D, IEEE 802.1w,
IEEE 802.1s, IEEE 802.1Q, IEEE 802.1p, IEEE 802.1ad, IEEE 802.1AB, IEEE 802.3az, IEEE 802.1X
Connectors: (1) RJ-45 console port, (4) 10/100/1000 RJ-45 ports, (4) 100/1000 SFP slots
Protocols: CSMA/CD
Technology: Store-and-forward switching architecture
MAC Address: 8K MAC address table
Backplane: 16 Gbps
Dimensions: Width: 8.66” [220 mm] x Depth: 6.26” [159 mm] x Height: 1.69” [44 mm]
Power Input: Internal power: 100-240VAC
Operating Temp.: 0°C to 40°C
Humidity: 5% to 90% (non-condensing)
Weight: 3.85 lbs. [1.75 kg]
Certifications: Safety: LVD. Emissions: FCC Class A, CE.
Warranty: Lifetime

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Cautions and Warnings
Cautions indicate that there is the possibility of poor equipment performance or potential damage to the
equipment. Warnings indicate that there is the possibility of injury to person.
Cautions and Warnings appear here and may appear throughout this manual where appropriate. Failure to read
and understand the information identified by this symbol could result in poor equipment performance, damage to
the equipment, or injury to persons.
Caution: While installing or servicing the power supply module, wear a grounding device and observe all
electrostatic discharge precautions. Failure to observe this caution could result in damage to, or failure of the power
module.
Warning: Do not connect the power module to an external power source before installing it into the chassis.
Failure to observe this warning could result in an electrical shock, even death.
Warning: Equipment grounding is vital to ensure safe operation. The installer must ensure that the power module
is properly grounded during and after installation. Failure to observe this warning could result in an electric shock,
even death.
Warning: A readily accessible, suitable National Electrical Code (NEC) or local electrical code approved disconnect
device and branch-circuit protector must be part of the building's installed wiring to accommodate permanently
connected equipment. Failure to observe this warning could result in an electric shock, even death.
Warning: Turn any external power source OFF and ensure that the power module is disconnected from the
external power source before performing any maintenance. Failure to observe this warning could result in an
electrical shock, even death.
Warning: Ensure that the disconnect device for the external power source is OPEN (turned OFF) before
disconnecting or connecting the power leads to the power module. Failure to observe this warning could result in an
electric shock, even death.

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Hardware Description
Switch Architecture
The switch provides a wire-speed, non-blocking switching fabric. This allows wire-speed transport of multiple
packets at low latency on all ports simultaneously. The switch also features full-duplex capability on all ports, which
effectively doubles the bandwidth of each connection.
This switch uses store-and-forward technology to ensure maximum data integrity. With this technology, the entire
packet must be received into a buffer and checked for validity before being forwarded. This prevents errors from
being propagated throughout the network.
Network Management Options
The switch can be managed over the network with a web browser or Telnet application. The switch includes a built-
in network management agent that allows it to be managed in-band using SNMP or RMON (Groups 1, 2, 3, 9)
protocols. It also has an RJ45 console port connector on the front panel for out-of-band management. A PC may be
connected to this port for configuration and monitoring out-of-band via a null-modem serial cable. (See Appendix B
for wiring options.)
Note: For a detailed description of the management features, refer to the related manual.
Front Panel
Back Panel

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1000BASE-T Ports
The switch contains 4 10/100/1000BASE-T RJ-45 ports. All RJ-45 ports support automatic MDI/MDI-X operation,
auto-negotiation and IEEE 802.3x auto-negotiation of flow control, so the optimum data rate and transmission can
be selected automatically.
SFP Transceiver Slots
SM4T4DPA supports the Small Form Factor Pluggable (SFP) transceiver. Please visit our SFP webpage for details
on the optional SFP modules.
Port and System Status LEDS
The SM4T4DPA switch includes a display panel for system and port indications that simplify installation and
network troubleshooting. The LEDs, which are located on left hand side of the front panel for easy viewing. Details
are shown below and described in the following tables.
Table 1: Port Status LEDs
LED Condition Status
TP (Link/ACT) Green Lit Green when TP link good
Blinks when any traffic is present
TP SPEED Green Lit Green when TP link on 1000Mbps
Blinks when TP link on 100Mbps
Off when TP link on 10Mbps
SFP (Link/ACT) Green/Amber Lit Green when SFP link on 1000Mbps speed
Lit Amber when SFP link on 100Mbps speed
Blinks when any traffic is present
Table 2: System Status LEDs
LED Condition Status
Power Green OFF Lit when power is coming up
AC Input
There is a power sockets on the rear panel of the switch. For normal power supply, the Switch has a standard
power socket for the AC power cord.
Figure 3: Power Supply Socket
Power Supply Socket

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Network Planning
Introduction to Switching
A network switch allows simultaneous transmission of multiple packets; it can partition a network more efficiently
than bridges or routers. Thus the switch has been recognized as one of the most important device for today’s
networking technology.
When performance bottlenecks are caused by congestion at the network access point such as file server, the
device can be connected directly to a switched port. And, by using full-duplex mode, the bandwidth of the dedicated
segment can be doubled to maximize throughput.
When networks are based on repeater (hub) technology, the distance between end stations is limited by a
maximum hop count. However, a switch can subdividing the network into smaller and more manageable segments,
and linking them to the larger network than it turns the hop count back to zero and removes the limitation.
A switch can be easily configured in any Ethernet, Fast Ethernet, or Gigabit Ethernet network to significantly
increase bandwidth while using conventional cabling and network cards.
Application Examples
The Switch implements 4 Gigabit Ethernet TP ports and 4 slots for the removable SFP module which supports
comprehensive types of fiber connection, such as LC and BiDi-LC modules. It is not only designed to segment your
network, but also to provide a wide range of options in setting up network connections. Some typical applications
are described below.
•Remote site application is used in Enterprise or SMB
•Peer-to-peer application is used in two remote offices
•Office network
•High Performance Requirement environment
•Advance Security for network safety application
•Suitable for data/ voice and video conference application
Peer-to-peer Network Connection

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Network Connection between Remote Site and Central Site
Office Network Connection

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Installation
Selecting a Site
The Switch can be mounted in a standard 19-inch equipment rack (Via Optional Rack mount Kit) or on a flat
surface. Be sure to follow the guidelines below when choosing a location.
◆The site should:
Be at the center of all the devices you want to link and near a power outlet.
Be able to maintain its temperature within 0 to 40°C (32 to 104 °F) and its humidity within 10% to 90%, non-
condensing.
Be accessible for installing, cabling and maintaining the devices.
Allow the status LEDs to be clearly visible.
◆Make sure the twisted-pair Ethernet cable is always routed away from power lines, radios, transmitters or any
other electrical interference.
◆Make sure that SM4T4DPA Switch is connected to a separate grounded power outlet that provides 100 to 240
VAC, 50 to 60 Hz.
Ethernet Cabling
To ensure proper operation when installing the switch into a network, make sure that the current cables are suitable
for 100BASE-TX or 1000BASE-T operation. Check the following criteria against the current installation of your
network:
◆Cable type: Unshielded twisted pair (UTP) or shielded twisted pair (STP) cable with RJ-45 connectors; Category
5 or Category 5e with maximum length of 100 meters is recommend 100BASE-TX, and Category 5e or 6 with
maximum length of 100 meters is recommend for 1000BASE-T.
◆Protection from radio frequency interference emissions.
◆Electrical surge suppression.
◆Separation of electrical wires and data based network wiring.
◆Safe connections with no damaged cables, connectors or shields.
RJ-45 Connections SFP Transceiver

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Equipment Checklist
After unpacking this switch, please check the contents to be sure you have received all the components. Then,
before beginning the installation, be sure you have all other necessary installation equipment.
Package Contents
□SM4T4DPA Management Switch
□Four adhesive rubber feet
□Mounting Accessory (for 19” Rack Shelf, Optional)
□This Installation Guide
□One AC Power Cord
□One RS-232 to RJ-45 Console Cable
Note: Notify your sales representative immediately if any of the aforementioned items is missing or damaged.
Warning: The mini-GBICs are Class 1 laser devices. Avoid direct eye exposure to the beam coming from the
transmit port.
Mounting
The switch can be mounted in a standard 19-inch equipment rack or on a desktop or shelf. Mounting instructions
for each type of site as follows.
Rack Mounting
Before rack mounting the switch, please pay attention to the following factors:
□Temperature: Since the temperature within a rack assembly may be higher than the ambient room
temperature, check that the rack-environment temperature is within the specified operating temperature
range (0 to 40 °C).
□Mechanical Loading: Do not place any equipment on top of a rack-mounted unit.
□Circuit Overloading: Be sure that the supply circuit to the rack assembly is not overloaded.
□Grounding: Rack-mounted equipment should be properly grounded.
To Rack-mount Devices:
Step 1. Attach the brackets to the device using the screws provided in the Mounting Accessory.
Attaching the Brackets
Step 2. Mount the device in the rack (Via Optional Rack-Mount kit), using four rack-mounting screws (not provided).
Be sure to secure the lower rack-mounting screws first to prevent the brackets being bent by the weight of the
switch.

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Installing the switch in a Rack
Step 3. If installing a single switch only, turn to “Connection to a Power Source” at the end of this chapter.
Step4. If installing multiple switches, mount them in the rack, one below the other, in any order.
Desktop or Shelf Mounting
Step 1. Attach the four adhesive rubber feet to the bottom of the first switch.
Attaching the Adhesive Rubber Feet
Step 2. Set the device on a flat surface near an AC power source, making sure there are at least two inches of
space on all sides for proper air flow.
Step 3. If installing a single switch only, go to “Connecting to a Power Source” at the end of this Chapter.
Step4. If installing multiple switches, attach four adhesive feet to each one. Place each device squarely on top of
the one below, in any order.

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Installing an Optional SFP Transceiver
You can install or remove a mini-GBIC SFP from a mini-GBIC slot without having to power off the switch.
Note:
□The SFP ports operate only at full duplex. Half duplex operation is not supported.
□Ensure the network cable is NOT connected when you install or remove an SFP.
Inserting an SFP Transceiver into a Slot
To Install a SFP transceiver, do the following:
Step 1. Consider network and cabling requirements to select an appropriate SFP transceiver type.
Step 2. Insert the transceiver with the optical connector facing outward and the slot connector facing down. Note
that SFP transceivers are keyed so they can only be installed in one orientation.
Step 3. Slide the SFP transceiver into the slot until it clicks into place.
Note: SFP transceivers are not provided in the switch package.
Connecting to a Power Source
You can plug or remove the power cord from AC power socket to switch the power on and off.
Inserting the Power Cord to AC Power Socket
Step 1. Insert the power cable plug directly into the AC Socket located at the back of the switch.
Step 2. Plug the other end of the cable into a grounded, 3-Pin, AC power source.
Step 3. Check the front-panel LEDs as the device is powered on to be sure the POWER LED is lit. If not, check that
the power cable is correctly plugged in.
Warning: For International use, you may need to change the AC line cord. You must use a line cord set that has
been approved for the socket type in your country.

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Connecting to the Console Port
The RJ-45 serial port on the switch’s front panel is used to connect to the switch for out-of-band console
configuration.
The command-line-driven configuration program can be accessed from a terminal or a PC running a terminal
emulation program. The pin assignments used to connect to the serial port are provided below.
Serial Port (RJ-45) Pin-Out
Wiring Map for the Serial Cable
Table 3: Serial Cable Wiring
Switch’s 8-Pin Serial Port Null Modem Cable PC’s 9-Pin DTE Port
2 RXD (receive data) ◄----------------- 3 TXD (transmit data)
3 RXD (receive data) ---------------─--►2 RXD (receive data)
5 SGND (Signal ground) ---------------------- 5 SGND (Signal ground)
Note: No other pins are used.
Plug in the Console Port
The serial port’s configuration requirements are as follows:
◆Default Baud rate—115,200 bps
◆Character Size—8 Characters
◆Parity—None
◆Stop bit—One
◆Data bits—8
◆Flow control—none

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Operation of Web-based Management
The default values of the managed switch are listed below:
•IP Address 192.168.1.77
•Subnet Mask 255.255.255.0
•Default 192.168.1.254
•Username admin
•Password admin
After the switch has finished configuration in the CLI via the switch’s serial interface, you can browse it. For
instance, type http://192.168.1.77 in the address row in a browser, and it will show the following screen and ask you
to enter a username and password in order to login and access authentication. The default username and
password are both “admin”. For first time use, enter the default username and password, and then click the
<Login> button. The login process now is completed.
SM4T4DPA Web User Interface:
Note: If you need to set other parameters, refer to the detail in the related. You can also access the Switch and
click the "help" button under the web GUI and the switch will pop-up help content on how to set the parameters:

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Making Network Connections
Connecting Network Devices
The switch is designed to be connected to 10, 100 or 1000Mbps network cards in PCs and servers, as well as to
other switches and hubs. It may also be connected to remote devices using optional SFP transceivers.
Twisted-Pair Devices
Each device requires an unshielded twisted-pair (UTP) cable with RJ-45 connectors at both ends. Use Category 5,
5e or 6 cable for 1000BASE-T connections, Category 5 or better for 100BASE-TX connections.
Cabling Guidelines
The RJ-45 ports on the switch support automatic MDI/MDI-X pinout configuration, so you can use standard straight-
through twisted-pair cables to connect to any other network device (PCs, servers, switches, routers, or hubs).
See Appendix B for further information on cabling.
Caution: Do not plug a phone jack connector into an RJ-45 port. This will damage the switch. Use only twisted-pair
cables with RJ-45 connectors that conform to FCC standards.
Connecting to PCs, Servers, Hubs and Switches
Step 1. Attach one end of a twisted-pair cable segment to the device’s RJ-45 connector.
Making Twisted-Pair Connections
Step 2. If the device is a network card and the switch is in the wiring closet, attach the other end of the cable
segment to a modular wall outlet that is connected to the wiring closet. (See the section “Network Wiring
Connections.”) Otherwise, attach the other end to an available port on the switch.
Make sure each twisted pair cable does not exceed 100 meters (328 ft) in length.
Note: Avoid using flow control on a port connected to a hub unless it is actually required to solve a problem.
Otherwise, back pressure jamming signals may degrade overall performance for the segment attached to
the hub.
Step 3. As each connection is made, the Link LED (on the switch) corresponding to each port will light green (1000
Mbps) or amber (100 Mbps) to indicate that the connection is valid.

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Network Wiring Connections
The punch-down block is an integral part of many of the newer equipment racks. It is actually part of the patch
panel. Instructions for making connections in the wiring closet with this type of equipment follows.
Step 1. Attach one end of a patch cable to an available port on the switch, and the other end to the patch panel.
Step 2. If not already in place, attach one end of a cable segment to the back of the patch panel where the punch-
down block is located, and the other end to a modular wall outlet.
Step 3. Label cables to simplify future troubleshooting. See “Cable Labeling and Connection Records” on page 24.
Network Wiring Connections
Fiber Optic SFP Devices
An optional Gigabit SFP transceiver can be used for a backbone connection between switches, or for connecting to
a high-speed server.
Each single-mode fiber port requires 9/125 micron single-mode fiber optic cable with an LC connector at both ends.
Each multimode fiber optic port requires 50/125 or 62.5/125 micron multimode fiber optic cabling with an LC
connector at both ends.
Warning: This switch uses lasers to transmit signals over fiber optic cable. The lasers are inherently eye safe in
normal operation. However, user should never look directly at a transmit port when it is powered on.
Warning: When selecting a fiber SFP device, considering safety, make sure that it can function at a temperature
that is not less than the recommended maximum operational temperature of the product. You must also use an
approved Laser SFP transceiver.
Step 1. Remove and keep the LC port’s rubber plug. When not connected to a fiber cable, the rubber plug should
be replaced to protect the optics.
Step 2. Check that the fiber terminators are clean. You can clean the cable plugs by wiping them gently with a
clean tissue or cotton ball moistened with a little ethanol. Dirty fiber terminators on fiber optic cables will impair the
quality of the light transmitted through the cable and lead to degraded performance on the port.
Step 3. Connect one end of the cable to the LC port on the switch and the other end to the LC port on the other
device. Since LC connectors are keyed, the cable can be attached in only one orientation.

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Making Fiber Port Connections
Step 4. As a connection is made, check the Link LED on the switch corresponding to the port to be sure that the
connection is valid.
The fiber optic ports operate at 1 Gbps. The maximum length for fiber optic cable operating at Gigabit speed will
depend on the fiber type as listed under “1000 Mbps Gigabit Ethernet Collision Domain” on page 22.
Connectivity Rules
When adding hubs to your network, please note that because switches break up the path for connected devices
into separate collision domains, you should not include the switch or connected cabling in your calculations for
cascade length involving other devices.
1000BASE-T Cable Requirements
All Category 5 UTP cables that are used for 100BASE-TX connections should also work for 1000BASE-T, providing
that all four wire pairs are connected. However, it is recommended that for all critical connections, or any new cable
installations, Category 5e or Category 6 cable should be used. The Category 5e and 6 specifications include test
parameters that are only recommendations for Category 5. So the first step in preparing existing Category 5 cabling
for running 1000BASE-T is a simple test of the cable installation to be sure that it complies with the IEEE 802.3-
2005 standards.
Cable Labeling and Connection Records
When planning a network installation, it is essential to label the opposing ends of cables and to record where each
cable is connected. This will allow user to easily locate inter-connected devices, isolate faults and change your
topology without need for unnecessary time consumption.
To best manage the physical implementations of your network, follow these guidelines:
•Clearly label the opposing ends of each cable.
•Using your building’s floor plans, draw a map of the location of all network-connected equipment. For
each piece of equipment, identify the devices to which it is connected.
•Note the length of each cable and the maximum cable length supported by the switch ports.
•For ease of understanding, use a location-based key when assigning prefixes to your cable labeling.
•Use sequential numbers for cables that originate from the same equipment.
•Differentiate between racks by naming accordingly.
•Label each separate piece of equipment.
•Display a copy of your equipment map, including keys to all abbreviations at each equipment rack.