DS3820EPSA | 8-Port Industrial 10/100 Switch

Description

Product Introduction

Think of this as the network backbone for your Speedtronic control system. The DS3820EPSA isn’t just a dumb hub—it’s a managed Layer 2 switch with traffic prioritization baked in. It sits in the main control cabinet, connecting the Mark VI processor to the HMI workstations, the exciter bridge interface, and the remote I/O racks. Without it, your turbine is effectively blind.

Compared to the older DS3800EPSA, the “20” revision adds two critical features: port mirroring for diagnostics (without interrupting traffic) and SNMP support for network monitoring. The older unit required a serial console for any configuration; now you can pull up a web interface and see collision counters, bandwidth usage, and error frames in real time. Field data shows roughly 40% fewer unexplained network timeouts on the DS3820 revision. That said, the port count and physical form factor stayed identical—it’s a mechanical drop-in.

Key Technical Specifications

Compatible Replacement Models

Frequently Asked Questions (FAQ)

Q: Can I manage the DS3820EPSA through the Mark VI HMI?
Not directly. The HMI communicates through the switch, not to it. You need a separate laptop with a browser or a serial console connection to configure the switch. GE’s default IP is 192.168.1.100, with a subnet mask of 255.255.255.0. If that’s been changed, you’ll need to connect via the console port and do a factory reset—or, more likely, read the factory label on the unit (we’ve seen plants lose the sticker and spend hours hunting the IP).

Q: Can I use standard Cat5e cables, or do I need the GE-specified cable?
Standard Cat5e or Cat6 patch cables work fine. However, be careful with industrial-grade cable (shielded, braided) if you’re in a high-EMI environment—the DS3820EPSA has internal surge suppression, but heavy VFDs can induce noise on the copper. If you’re running cables longer than 50 meters, we recommend fiber-to-copper media converters; the switch doesn’t have SFP ports. To be frank, we’ve seen plants use unshielded cable in a VFD-heavy cabinet and get dropped frames every 10 minutes—use shielded cables in those scenarios.

Q: My switch shows a steady red Fault LED. What does that mean?
The Fault LED typically indicates either a power supply issue (voltage below 18V) or an internal switch self-test failure during POST. First, check your 24V supply with a multimeter at the terminal block. If voltage is clean, cycle power—the switch does a self-test on boot and will clear the LED if it’s a transient. If the LED persists, you likely have a failed internal DC-DC converter; we’ve seen three of those in the last two years. Return it for repair or replacement.

Q: How do I configure port mirroring?
Access the web interface at port 80, go to “Port Configuration,” and select “Mirroring” from the menu. You can mirror any port (source) to any other port (destination). Common use case: mirror the port connected to your main I/O rack to an empty port, then plug in a Wireshark laptop to troubleshoot network issues. The mirror port will send outbound traffic only—you can’t see incoming traffic on the mirrored port (that’s a limitation of the chipset, not a GE bug). Budget about 15 minutes to set this up once.

Q: What’s the MTBF rating for this switch?
GE specifies 200,000 hours at 25°C. In reality, we see the power supply capacitors age faster—typically 8-10 years in a 40°C cabinet. The good news is the failure mode is usually gradual (intermittent resets) rather than catastrophic. If your switch is over 8 years old and you’ve had one or two unexplained network resets, we’d recommend swapping it proactively. The board cost is a fraction of the cost of one turbine trip.

Q: Does the DS3820EPSA support VLANs?
Yes, it supports up to 16 802.1Q VLANs. This is useful if you’re separating control traffic (high priority) from monitoring traffic (low priority). For example, assign your exciter and turbine control devices to VLAN 10 with high QoS, and assign your asset management PCs to VLAN 20 with best-effort. The switch processes VLAN tagging at line rate—no measurable delay. Just ensure your downstream devices (HMI, DCS) are also VLAN-capable; otherwise, the switch will strip tags by default.

Q: I’m replacing a damaged switch. Do I need to reload the firmware?
Maybe. The DS3820EPSA stores configuration in NVRAM, but the firmware is flash-based. If your unit is from a recent batch, the firmware is likely current (we typically see version 2.3.4 or higher). If you’re buying surplus, we can confirm the firmware revision before shipping. If you need to upgrade, GE’s firmware package is about 6 MB and takes about 4 minutes to upload via TFTP. We can provide the firmware files—though you’ll need the GE Toolbox software to perform the upload.

Q: What’s the typical lead time if I order today?
We maintain 2-3 units in our US warehouse at any given time. For US orders, ground shipping is 2-3 business days; overnight is available if your order is in by 2 PM EST. International: typically 5-7 business days via DHL, but customs in certain regions (we’re looking at you, Brazil) can add an extra 2-3 days. We recommend air shipping and using a customs broker to avoid the typical delays.

Q: Can I stack two DS3820EPSA units for redundancy?
Not directly. The DS3820EPSA doesn’t support stacking protocols like VSS or VPC. For true redundancy, you’d run two separate switches in a ring topology with STP (spanning tree protocol) enabled. The Mark VI controller will detect the link failure and route traffic through the secondary path—but the failover takes about 2-3 seconds, which is acceptable for most turbine control loops. Critical loops (like overspeed protection) should still use hardwired relays, not Ethernet. Don’t ask us why—just trust the field experience.

FOXBORO FBMSVH
A-B 80190-560-01-R
PROSOFT 5205-DFNT-PDPS
GE IC693CPU374