ISW-621S15
For unattended and critical infrastructure deployments, the ISW-621S15 provides a redundant dual power input with polarity reverse protection accepting 12 to 48 V DC — covering 12 V, 24 V and 48 V industrial supply rails from a single hardware SKU — and a relay output alarm (1A @ DC 24V) that activates on power supply failure to alert a supervisory system or SCADA before communication is lost. Ethernet ports are protected to 6000 VDC ESD and the power line to 6000 VDC EFT surge, with UL, cUL, CE and FCC Class A certification and IEC60068 shock and vibration testing confirming suitability for panel, cabinet and substation installations.
Key Features
- 2× 100Base-FX SC Single-Mode Fibre — 15km at 1310nm: Two SC-interface fibre ports transmit at 100 Mbps over 9/125μm single-mode fibre cable for distances up to 15 km at 1310 nm wavelength — the ISW-621S15 connects a panel-mounted copper Ethernet segment to a distant equipment room, substation or remote I/O cabinet over existing single-mode infrastructure without an intermediate repeater or managed switch; launch power max −7 dBm, receive sensitivity −28 dBm, max input power −8 dBm for link budget planning
- 4× 10/100Base-TX RJ45 — Auto-Negotiation and Auto-MDI/MDI-X: Four copper ports auto-negotiate 10 or 100 Mbps and auto-sense cable polarity (MDI/MDI-X), eliminating the need for crossover cables between the ISW-621S15 and connected devices; 10Base-T and 100Base-TX operation is supported over Cat. 5 cabling to 100 metres; full-duplex flow control follows IEEE 802.3x pause frame; half-duplex uses back pressure — ensuring seamless integration with PLCs, HMIs, I/O controllers and SCADA terminals already installed at the panel
- 1.2 Gbps Non-Blocking Switch Fabric — Store-and-Forward, 2K MAC Table: The 1.2 Gbps switch fabric provides full wire-speed forwarding across all six ports with no internal bottleneck — wire-speed throughput is 0.89 Mpps at 64-byte minimum frame size; store-and-forward architecture validates frame integrity before forwarding, discarding errored frames before they reach downstream devices; 2K MAC address entries and 1Mbit packet buffer accommodate standard industrial Ethernet topologies with multiple PLCs, drives, I/O nodes and SCADA terminals on the copper segment
- Redundant 12–48 VDC Input with Polarity Reverse Protection: Two independent power input terminals accept 12 to 48 V DC simultaneously — if the primary supply fails, the secondary takes over with no switch restart; polarity reverse protection prevents damage from miswired supply connections during installation or maintenance; the 12–48 V range covers 12 V vehicle and telecom supplies, 24 V DIN-rail industrial supplies and 48 V utility and telecom rack supplies from a single switch model without a voltage adapter or separate SKU
- Power Fail Relay Output — 1A at DC 24V for SCADA Integration: A dry-contact relay output rated at 1A at DC 24V activates when either power input fails, enabling supervisory SCADA systems, PLCs or remote monitoring systems to receive a hardware alarm before network communication degrades; this is particularly important in unattended remote installations — substations, pipeline monitoring stations, water treatment sites — where a silent power supply failure would otherwise go unnoticed until a communication timeout is detected at the control centre
- 6000 VDC ESD Protection on Ethernet Ports and 6000 VDC EFT Surge on Power Line: All four copper RJ45 Ethernet ports incorporate 6000 VDC electrostatic discharge protection against static buildup from cable handling and field connections in dry, low-humidity industrial environments; the power input terminal provides 6000 VDC electrical fast transient surge protection against switching transients from contactors, motor drives and relay coils sharing the 24 V supply rail — a common source of surge damage to unprotected electronics in machine control cabinets
- IP-30, DIN-Rail and Wall Mount, 135 × 87.8 × 32 mm, 442 g: The IP-30 metal chassis resists solid particle and finger-contact ingress in open panel and cabinet installations; the 135 × 87.8 × 32 mm form factor occupies 7.5 mm of DIN-rail width and a 32 mm profile depth, fitting inside standard control cabinet door cut-outs; a wall-mount ear is included for surface-mounting in enclosures and junction boxes without a DIN-rail; UL, cUL, CE and FCC Class A certification plus IEC60068-2-27 shock, IEC60068-2-6 vibration and IEC60068-2-32 free-fall testing confirm mechanical and regulatory compliance
Application Use Cases
Industrial Panel to Remote Equipment Room — Copper-to-Fibre Conversion
The most common ISW-621S15 deployment is connecting the copper Ethernet segment inside a machine control panel or MCC room to a fibre backbone link running to a remote equipment room, server room or operations centre up to 15 km away. Four RJ45 ports in the panel connect to PLCs, variable speed drives, HMI panels and I/O modules; both 100Base-FX SC ports connect to a matching fibre switch at the other end of the single-mode run. The unmanaged, plug-and-play architecture requires no commissioning, IP configuration or management overhead — the ISW-621S15 forwards frames transparently as a Layer 2 switch as soon as power and fibre are connected.
Substation and Power Distribution Network
In electrical substations and power distribution installations, the ISW-621S15 sits inside a protection relay panel or RTU cabinet, connecting local IED and SCADA devices via its four copper RJ45 ports and linking the substation LAN to the control centre or master station over single-mode fibre. The 6000 VDC EFT surge protection on the power line and 6000 VDC ESD on Ethernet ports address the high electromagnetic interference environment in HV/MV substations where switching transients and earth potential differences across long cable runs are routine operational conditions. The power fail relay output integrates directly with the substation RTU's digital input channels for supervisory alarm reporting without a separate power monitor relay.
Water, Wastewater and Utilities Remote Monitoring
At pump stations, water treatment plants and utility monitoring sites separated from the SCADA control room by more than 2 km, the ISW-621S15 provides the Ethernet segment at the remote site connected to instruments, flow meters, RTUs and local control panels via its four copper ports, whilst the single-mode fibre ports carry data back to the control room over the plant's existing single-mode fibre infrastructure. The redundant 12–48 VDC power input accepts supply from the site's 24 V instrument bus, and the power fail relay output alerts the SCADA system before a power supply degradation causes a communication outage — maintaining the availability record required under utility service level agreements.
Inter-Building Ethernet Backbone at Manufacturing Sites
Large manufacturing sites with multiple production buildings, warehouses and logistics centres typically run single-mode fibre between buildings in buried conduit. The ISW-621S15 terminates the single-mode fibre link at each building's local distribution panel and provides four copper RJ45 ports for local device connections — machine controllers, barcode readers, label printers, pick-to-light controllers and line HMI terminals. At 15 km maximum reach, a single ISW-621S15 pair covers the diameter of almost any single-site campus without an intermediate regenerator, repeater or powered splice point in the fibre run.
Mobile and Harsh-Environment Installations
The ISW-621S15's 12–48 VDC input and IP-30 metal chassis make it suitable for mobile plant and harsh fixed installations: rail vehicles, mobile command units and outdoor junction cabinets running 12 V or 24 V DC from batteries, solar regulators or vehicle alternators all fall within the input voltage range. IEC60068-2-27 shock and IEC60068-2-6 vibration testing confirms mechanical robustness for installations subject to transport vibration, vehicle dynamics and mechanical shock loads that would cause solder joint fatigue or component displacement in consumer-grade network hardware not rated to IEC60068 standards.
Why Choose the ISW-621S15
15km Single-Mode Fibre Reach Without a Managed Switch or Media Converter
Achieving 15 km fibre reach on an industrial DIN-rail switch without Layer 2 management overhead is the ISW-621S15's primary advantage over both shorter-reach unmanaged switches and over media converter solutions. A media converter approach to the same link requires two media converters, two power supplies, two DIN-rail mounting positions and two device failure modes — the ISW-621S15 integrates all copper and fibre switching into one chassis on one DIN-rail slot with one power connection. For system integrators building panels where every centimetre of DIN-rail and every watt of panel power budget is accounted for, consolidating four copper ports and two 15km fibre ports into a 32mm deep, 442g switch is a meaningful reduction in panel engineering complexity.
Redundant Power and Relay Alarm for Unattended Critical Infrastructure
Unmanaged switches are frequently selected precisely because they require no ongoing management — but that means a power supply failure in an unattended remote installation can go undetected until a communication timeout triggers an alarm at the control centre, potentially minutes or hours after the failure. The ISW-621S15's redundant power input with automatic failover and the dedicated relay alarm output break this failure mode: a primary supply fault triggers the relay immediately, whilst the secondary supply maintains network communication. The supervisory SCADA receives a hardware alarm contact input from the relay before any communication degradation, enabling preventive dispatch of a maintenance technician rather than emergency response after a network outage.
6kV ESD and EFT Protection Rated to IEC60068 — CE, FCC, UL and cUL Certified
The combination of 6000 VDC ESD protection on all Ethernet ports and 6000 VDC EFT surge protection on the power line addresses the two most common failure mechanisms for network hardware in industrial environments: static discharge from field cable connection and switching transients from coils, contactors and motor drives on the shared 24 V supply rail. These protection levels, combined with UL/cUL and CE/FCC Class A certification and IEC60068-2-27 shock and IEC60068-2-6 vibration compliance, cover the requirements for panel review and certification under both European (CE machinery directive) and North American (UL 508A panel standards) industrial installation codes without sourcing separate switches for different market territories.
Frequently Asked Questions
What is the maximum fibre distance of the ISW-621S15?
The ISW-621S15 supports 100Base-FX transmission over single-mode 9/125μm fibre at 1310nm wavelength up to a maximum distance of 15 km. The fibre ports use SC-type connectors. For shorter intra-building distances (up to 2 km), the ISW-621 multi-mode variant uses 50/125μm fibre and offers higher launch power margin for typical multi-mode fibre patch runs within a single building or campus.
What is the difference between the ISW-621 and ISW-621S15?
The only difference between the ISW-621 and ISW-621S15 is the fibre specification. The ISW-621 uses multi-mode 50/125μm fibre with 1310nm wavelength and 2km maximum reach; the ISW-621S15 uses single-mode 9/125μm fibre with 1310nm wavelength and 15km maximum reach. All other specifications — copper ports, switch fabric, MAC table, power input, redundant power, relay alarm, ESD/EFT protection, mounting options, dimensions and certifications — are identical between the two models.
What power supply does the ISW-621S15 require?
The ISW-621S15 accepts 12 to 48 V DC on two independent redundant power input terminals. Both terminals can be connected to independent power sources simultaneously; if one supply fails, the other maintains switch operation without interruption. The input includes polarity reverse protection to prevent damage from miswired connections. Maximum power consumption is 11.6 W (40 BTU). An optional 24 V power adapter is not included and must be sourced separately.
Does the ISW-621S15 have a power failure alarm output?
Yes. The ISW-621S15 provides a relay dry-contact output rated at 1A at DC 24V that activates when either power input fails. This relay output can be wired to a SCADA digital input, a PLC alarm input or a remote monitoring unit to generate a supervisory alarm on power supply failure — enabling early detection of power supply degradation at unattended remote installations before a network communication outage occurs.
Is the ISW-621S15 a managed switch? Does it support VLANs or QoS?
No. The ISW-621S15 is a fully unmanaged switch with no management interface, no VLAN support and no QoS configuration. It operates as a transparent Layer 2 switch that forwards Ethernet frames based on MAC address learning with no configuration required — power on, connect devices and cables, and the switch operates immediately. For installations requiring VLAN segmentation, IGMP snooping, Spanning Tree or port-based QoS on industrial fibre links, Planet's managed industrial switch range should be considered instead.
For unattended and critical infrastructure deployments, the ISW-621S15 provides a redundant dual power input with polarity reverse protection accepting 12 to 48 V DC — covering 12 V, 24 V and 48 V industrial supply rails from a single hardware SKU — and a relay output alarm (1A @ DC 24V) that activates on power supply failure to alert a supervisory system or SCADA before communication is lost. Ethernet ports are protected to 6000 VDC ESD and the power line to 6000 VDC EFT surge, with UL, cUL, CE and FCC Class A certification and IEC60068 shock and vibration testing confirming suitability for panel, cabinet and substation installations.
Key Features
- 2× 100Base-FX SC Single-Mode Fibre — 15km at 1310nm: Two SC-interface fibre ports transmit at 100 Mbps over 9/125μm single-mode fibre cable for distances up to 15 km at 1310 nm wavelength — the ISW-621S15 connects a panel-mounted copper Ethernet segment to a distant equipment room, substation or remote I/O cabinet over existing single-mode infrastructure without an intermediate repeater or managed switch; launch power max −7 dBm, receive sensitivity −28 dBm, max input power −8 dBm for link budget planning
- 4× 10/100Base-TX RJ45 — Auto-Negotiation and Auto-MDI/MDI-X: Four copper ports auto-negotiate 10 or 100 Mbps and auto-sense cable polarity (MDI/MDI-X), eliminating the need for crossover cables between the ISW-621S15 and connected devices; 10Base-T and 100Base-TX operation is supported over Cat. 5 cabling to 100 metres; full-duplex flow control follows IEEE 802.3x pause frame; half-duplex uses back pressure — ensuring seamless integration with PLCs, HMIs, I/O controllers and SCADA terminals already installed at the panel
- 1.2 Gbps Non-Blocking Switch Fabric — Store-and-Forward, 2K MAC Table: The 1.2 Gbps switch fabric provides full wire-speed forwarding across all six ports with no internal bottleneck — wire-speed throughput is 0.89 Mpps at 64-byte minimum frame size; store-and-forward architecture validates frame integrity before forwarding, discarding errored frames before they reach downstream devices; 2K MAC address entries and 1Mbit packet buffer accommodate standard industrial Ethernet topologies with multiple PLCs, drives, I/O nodes and SCADA terminals on the copper segment
- Redundant 12–48 VDC Input with Polarity Reverse Protection: Two independent power input terminals accept 12 to 48 V DC simultaneously — if the primary supply fails, the secondary takes over with no switch restart; polarity reverse protection prevents damage from miswired supply connections during installation or maintenance; the 12–48 V range covers 12 V vehicle and telecom supplies, 24 V DIN-rail industrial supplies and 48 V utility and telecom rack supplies from a single switch model without a voltage adapter or separate SKU
- Power Fail Relay Output — 1A at DC 24V for SCADA Integration: A dry-contact relay output rated at 1A at DC 24V activates when either power input fails, enabling supervisory SCADA systems, PLCs or remote monitoring systems to receive a hardware alarm before network communication degrades; this is particularly important in unattended remote installations — substations, pipeline monitoring stations, water treatment sites — where a silent power supply failure would otherwise go unnoticed until a communication timeout is detected at the control centre
- 6000 VDC ESD Protection on Ethernet Ports and 6000 VDC EFT Surge on Power Line: All four copper RJ45 Ethernet ports incorporate 6000 VDC electrostatic discharge protection against static buildup from cable handling and field connections in dry, low-humidity industrial environments; the power input terminal provides 6000 VDC electrical fast transient surge protection against switching transients from contactors, motor drives and relay coils sharing the 24 V supply rail — a common source of surge damage to unprotected electronics in machine control cabinets
- IP-30, DIN-Rail and Wall Mount, 135 × 87.8 × 32 mm, 442 g: The IP-30 metal chassis resists solid particle and finger-contact ingress in open panel and cabinet installations; the 135 × 87.8 × 32 mm form factor occupies 7.5 mm of DIN-rail width and a 32 mm profile depth, fitting inside standard control cabinet door cut-outs; a wall-mount ear is included for surface-mounting in enclosures and junction boxes without a DIN-rail; UL, cUL, CE and FCC Class A certification plus IEC60068-2-27 shock, IEC60068-2-6 vibration and IEC60068-2-32 free-fall testing confirm mechanical and regulatory compliance
Application Use Cases
Industrial Panel to Remote Equipment Room — Copper-to-Fibre Conversion
The most common ISW-621S15 deployment is connecting the copper Ethernet segment inside a machine control panel or MCC room to a fibre backbone link running to a remote equipment room, server room or operations centre up to 15 km away. Four RJ45 ports in the panel connect to PLCs, variable speed drives, HMI panels and I/O modules; both 100Base-FX SC ports connect to a matching fibre switch at the other end of the single-mode run. The unmanaged, plug-and-play architecture requires no commissioning, IP configuration or management overhead — the ISW-621S15 forwards frames transparently as a Layer 2 switch as soon as power and fibre are connected.
Substation and Power Distribution Network
In electrical substations and power distribution installations, the ISW-621S15 sits inside a protection relay panel or RTU cabinet, connecting local IED and SCADA devices via its four copper RJ45 ports and linking the substation LAN to the control centre or master station over single-mode fibre. The 6000 VDC EFT surge protection on the power line and 6000 VDC ESD on Ethernet ports address the high electromagnetic interference environment in HV/MV substations where switching transients and earth potential differences across long cable runs are routine operational conditions. The power fail relay output integrates directly with the substation RTU's digital input channels for supervisory alarm reporting without a separate power monitor relay.
Water, Wastewater and Utilities Remote Monitoring
At pump stations, water treatment plants and utility monitoring sites separated from the SCADA control room by more than 2 km, the ISW-621S15 provides the Ethernet segment at the remote site connected to instruments, flow meters, RTUs and local control panels via its four copper ports, whilst the single-mode fibre ports carry data back to the control room over the plant's existing single-mode fibre infrastructure. The redundant 12–48 VDC power input accepts supply from the site's 24 V instrument bus, and the power fail relay output alerts the SCADA system before a power supply degradation causes a communication outage — maintaining the availability record required under utility service level agreements.
Inter-Building Ethernet Backbone at Manufacturing Sites
Large manufacturing sites with multiple production buildings, warehouses and logistics centres typically run single-mode fibre between buildings in buried conduit. The ISW-621S15 terminates the single-mode fibre link at each building's local distribution panel and provides four copper RJ45 ports for local device connections — machine controllers, barcode readers, label printers, pick-to-light controllers and line HMI terminals. At 15 km maximum reach, a single ISW-621S15 pair covers the diameter of almost any single-site campus without an intermediate regenerator, repeater or powered splice point in the fibre run.
Mobile and Harsh-Environment Installations
The ISW-621S15's 12–48 VDC input and IP-30 metal chassis make it suitable for mobile plant and harsh fixed installations: rail vehicles, mobile command units and outdoor junction cabinets running 12 V or 24 V DC from batteries, solar regulators or vehicle alternators all fall within the input voltage range. IEC60068-2-27 shock and IEC60068-2-6 vibration testing confirms mechanical robustness for installations subject to transport vibration, vehicle dynamics and mechanical shock loads that would cause solder joint fatigue or component displacement in consumer-grade network hardware not rated to IEC60068 standards.
Why Choose the ISW-621S15
15km Single-Mode Fibre Reach Without a Managed Switch or Media Converter
Achieving 15 km fibre reach on an industrial DIN-rail switch without Layer 2 management overhead is the ISW-621S15's primary advantage over both shorter-reach unmanaged switches and over media converter solutions. A media converter approach to the same link requires two media converters, two power supplies, two DIN-rail mounting positions and two device failure modes — the ISW-621S15 integrates all copper and fibre switching into one chassis on one DIN-rail slot with one power connection. For system integrators building panels where every centimetre of DIN-rail and every watt of panel power budget is accounted for, consolidating four copper ports and two 15km fibre ports into a 32mm deep, 442g switch is a meaningful reduction in panel engineering complexity.
Redundant Power and Relay Alarm for Unattended Critical Infrastructure
Unmanaged switches are frequently selected precisely because they require no ongoing management — but that means a power supply failure in an unattended remote installation can go undetected until a communication timeout triggers an alarm at the control centre, potentially minutes or hours after the failure. The ISW-621S15's redundant power input with automatic failover and the dedicated relay alarm output break this failure mode: a primary supply fault triggers the relay immediately, whilst the secondary supply maintains network communication. The supervisory SCADA receives a hardware alarm contact input from the relay before any communication degradation, enabling preventive dispatch of a maintenance technician rather than emergency response after a network outage.
6kV ESD and EFT Protection Rated to IEC60068 — CE, FCC, UL and cUL Certified
The combination of 6000 VDC ESD protection on all Ethernet ports and 6000 VDC EFT surge protection on the power line addresses the two most common failure mechanisms for network hardware in industrial environments: static discharge from field cable connection and switching transients from coils, contactors and motor drives on the shared 24 V supply rail. These protection levels, combined with UL/cUL and CE/FCC Class A certification and IEC60068-2-27 shock and IEC60068-2-6 vibration compliance, cover the requirements for panel review and certification under both European (CE machinery directive) and North American (UL 508A panel standards) industrial installation codes without sourcing separate switches for different market territories.
Frequently Asked Questions
What is the maximum fibre distance of the ISW-621S15?
The ISW-621S15 supports 100Base-FX transmission over single-mode 9/125μm fibre at 1310nm wavelength up to a maximum distance of 15 km. The fibre ports use SC-type connectors. For shorter intra-building distances (up to 2 km), the ISW-621 multi-mode variant uses 50/125μm fibre and offers higher launch power margin for typical multi-mode fibre patch runs within a single building or campus.
What is the difference between the ISW-621 and ISW-621S15?
The only difference between the ISW-621 and ISW-621S15 is the fibre specification. The ISW-621 uses multi-mode 50/125μm fibre with 1310nm wavelength and 2km maximum reach; the ISW-621S15 uses single-mode 9/125μm fibre with 1310nm wavelength and 15km maximum reach. All other specifications — copper ports, switch fabric, MAC table, power input, redundant power, relay alarm, ESD/EFT protection, mounting options, dimensions and certifications — are identical between the two models.
What power supply does the ISW-621S15 require?
The ISW-621S15 accepts 12 to 48 V DC on two independent redundant power input terminals. Both terminals can be connected to independent power sources simultaneously; if one supply fails, the other maintains switch operation without interruption. The input includes polarity reverse protection to prevent damage from miswired connections. Maximum power consumption is 11.6 W (40 BTU). An optional 24 V power adapter is not included and must be sourced separately.
Does the ISW-621S15 have a power failure alarm output?
Yes. The ISW-621S15 provides a relay dry-contact output rated at 1A at DC 24V that activates when either power input fails. This relay output can be wired to a SCADA digital input, a PLC alarm input or a remote monitoring unit to generate a supervisory alarm on power supply failure — enabling early detection of power supply degradation at unattended remote installations before a network communication outage occurs.
Is the ISW-621S15 a managed switch? Does it support VLANs or QoS?
No. The ISW-621S15 is a fully unmanaged switch with no management interface, no VLAN support and no QoS configuration. It operates as a transparent Layer 2 switch that forwards Ethernet frames based on MAC address learning with no configuration required — power on, connect devices and cables, and the switch operates immediately. For installations requiring VLAN segmentation, IGMP snooping, Spanning Tree or port-based QoS on industrial fibre links, Planet's managed industrial switch range should be considered instead.
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