CT-N920

CorNet ARCNET Diagnostic Hub 4 Port Industrial Temperature Fiber ST 820 nm CE

Operating system independent ST connectors on network ports RJ11 connectors on link ports Cabling: 62.5/125um or 100/140um multimode fiber Link Budget 9.9dB with 62.5um or 15.4dB with 100um European CE compliance 120/220 VAC 50/60 Hz Operating: -40C to 75C, 0% to 95% (non-condensing)

A CorNet ARCNET Diagnostic Hub is an ideal way to combine fiber optic cabling in high noise environments with lower cost coaxial cabling in low-noise environments.

Why CorNet Hubs?

The CT-N800 & CT-N900 series of hubs were created to fill a need for an ARCNET hub with additional diagnostic capabilities for tracking down reconfiguration problems without resorting to the complexity and cost of an "intelligent hub". Some of these features include:

• Diagnostic indicators for each port to help isolate faulty connectors, cables, or ports by identifying the node with recon activity
• Expandable -- use link connectors to connect hubs without using up a port
• Wall and rack mountable -- mounting brackets are included
• Ideal for harsh environments
• Internal switching power supply uses less energy, and generates less heat, for more reliable long term operation.

ARCNET Specifications:

• Modified Token Passing Local Area Network
• 2.5 Megabaud transmission
• Supports up to 255 nodes
• Coax cable lengths up to 2000 ft (600m)
• Twisted pair cable lengths up to 400 ft (120m)
• Fiber cable lengths typically up to 8000 ft (2.5 km)

Before any CorNet product leaves our factory, we run it through an intensive burn-in procedure which isolates marginal components which other manufacturers'inspections often miss.

During our burn-in the adapters and hubs are turned on and connected to an operational LAN running diagnostic software. Then we raise the ambient temperature abnormally high for computer equipment (43C or 110F), creating even higher temperatures at the surface of the printed circuit board.

Our workmanship and quality control are second to none. If you're looking for reasonably priced ARCNET hubs and adapters for a harsh environment or just want the confidence of high reliability hubs and adapters for your office, the CorNet ARCNET products are for you.

DESCRIPTION

This is an ARCNET hub with diagnostic LEDs and linking ports. The CT-N800 series of hubs was created to fill a need for an ARCNET hub with additional diagnostic capabilities for tracking down reconfiguration problems without resorting to the complexity and cost of an "Intelligent Hub". The hubs maintain full output levels even when running at maximum temperature and data traffic loads. This stability is provided through the use of a switching regulator in the power supply and attention to detail in the output driver section. The switching regulator produces less heat and withstands brownouts better than a linear regulator. Proper thermal design ensures that heat produced in the output drivers is dissipated via convection air currents in any acceptable mounting position.

OPERATING ENVIRONMENT
Power :	120 VAC +6%/- 10% @ 160 mA or 240 VAC +6%/- 10% @ 80 mA, 50 Hz or 60 Hz
Operating Temperature:	0 to +55C
Humidity:	5% to 80% (non-condensing)
Arcnet LAN INTERFACE
Wavelength:	820nm to 850nm
Connectors:	Two ST connectors per port (Transmit [Tx] and Receive [Rx])
Max. Receiver Input Power:	-7.6dBm @ 25C, -8.2dBm @ 85C

Fiber Type (um)	62.5/125 100/140
Typical Transmitter Power	-12.0 dBm -6.5 dBm
Minimum Transmitter Power	-15.0 dBm -9.5 dBm
Typical Receiver Sensitivity	-27.5 dBm -27.5 dBm
Minimum Receiver Sensitivity	-24.9 dBm -24.9 dBm
Typical Link Budget	15.5 dB 21.0 dB
Minimum Link Budget	9.9 dB 15.4 dB

PHYSICAL SPECIFICATIONS

Height:
2.75 inches

Width:
8.5 inches

Depth:
7.5 inches (including connectors)

Weight:
5 pounds

Included with the hub are two mounting brackets and four bolts for attaching the brackets to the hub. A link cable and one terminator are included for expanding the hub configuration to add more ports or to connect hubs with different types of media. A detachable power cord is also included.

INSTALLATION CONSIDERATIONS

Coax Cable Type
RG62A/U 93 ohm with BNC connectors

Coax Distances
From node to hub 2000 ft.
Total network span up to 22,000 ft. (using standard time-outs)
Maximum of 10 active hubs may be between any two nodes on the network

Fiber Optic Cable Type:
Dual Fiber
Graded Index (Multi-Mode)
62.5/125um or 100/140um
ST connectors

Cable specifications include a standard connector loss for both ends of a single cable. It is recommended to allow 2dB of loss to allow for dirt and cracks in the connectors for any given link. Each fusion splice typically adds 0.25 dB loss, and barrel connector splices are the sum of the barrel connector and two end connector losses. All these factors result in loss along the line and must be considered

Maximum Distance per Segment:
A segment is the cable between two hubs or a hub and a card on the network. The maximum length of a segment of fiber optic cable is dependent on the quality, size, connectors, splices and rating of the fiber optic cable. The most important fiber optic cable specification is the attenuation per kilometer. In combination with the link budget shown previously, the maximum segment length can be calculated.

For example, consider a fiber optic cable with the following specifications:

• 62.5/125um
• Maximum attenuation 3.0 dB/Km
• No splices in entire cable length
• ST connectors on both ends
• Grade F, OFNR (UL Listed Riser)
• 850 nm

Max. Segment Length
= (Link budget - connector & splice losses - 2 dB)
------------------------------------------------
Attenuation
= (9.9 dB - 0 - 2 dB)
------------------------------------------------
3.0 dB/km
= 2.6 km [1.6 miles]

Maximum Network Span:
The maximum span defines the longest signal path length between any two nodes in the network. This determines the maximum end to end propagation delay. ARCNET controller chips have several internal timers based on the maximum propagation delay for a particular timeout level. A signal is allowed to pass through up to ten hub delays plus 2000ft [609m] of a coax cable at each segment to determine the standard propagation delay times. This becomes 22,000ft. [6705m] for a coax network. Since the velocity of propagation is lower in fiber optic cable, the network span is reduced. The maximum span for a network connected entirely with fiber optic cable using standard time-outs is approximately 18,500 ft. [5600 meters].

Before any unit can leave the factory, an intensive elevated temperature burn-in procedure is performed. During burn-in, the units are not only powered on but also connected to an operational LAN running diagnostic software. The ambient temperature in the burn-in chamber is raised to an abnormally high temperature for computer equipment creating even higher temperatures at the PCB surface of the unit itself. Our workmanship and quality control is focused on the goal of customer satisfaction.

Mounting
19" EIA rack mountable
Wall mountable
Stackable (up to 4 hubs)

CONFORMS TO THE FOLLOWING STANDARDS

EMC:
EN55022:1994 (Emissions)
CISPR 22 1993-12 Class A
FCC Part 15 Class A
EN 50082-1 (Immunity)
IEC 1000-4-2:1995 (IEC 801-2:1991)
IEC 1000-4-3:1995
IEC 1000-4-4:1995

Safety:
EN 60950:1992/A1:1993
IEC 950:1991+A1:1992+A2:1993
UL 1950, cUL (CSA 950 accepted equivalent)

Products are marked as certified to the CE standards.