DS38800NCID1C | Replace DS38800NCID Direct

Description

Product Introduction

The Mark VI doesn’t operate in a vacuum—it needs to talk to the rest of the plant. The DS38800NCID1C is the gateway that handles all that chatter: two Ethernet ports for the control network and HMI, and four serial ports for legacy devices (PLC, RTUs, or older instrumentation). It’s the translator that makes Modbus, DNP3, and GE’s own protocols coexist on the same backplane, passing data between the turbine controller and the outside world.

Compared to the DS38800NCID (non-1C revision), the “1C” suffix represents a significant hardware and firmware refresh. The Ethernet controller was upgraded from 10 Mbps to 10/100 Mbps auto-negotiation, and the serial ports now support baud rates up to 115.2 kbps (the older unit maxed out at 38.4 kbps). The onboard memory was doubled to 16 MB, allowing for larger protocol stacks and more concurrent connections. The terminal assignment changed slightly—the serial port pinouts were re-arranged to standardize on a common D-sub pinout (the older unit had non-standard assignments). Re-wiring is required if you’re upgrading from an older board. The -1C also added a hardware watchdog timer that resets the board if it locks up—field data shows a 90% reduction in field returns for communications lockups.

Key Technical Specifications

Compatible Replacement Models

Frequently Asked Questions (FAQ)

Q: What protocols does the NCID1C support out of the box?
It comes pre-loaded with GE’s SRTP (for HMI communication), Modbus TCP (client and server), Modbus RTU (serial), and DNP3 (serial and IP). Profibus DP requires an external converter module (GE’s PB401 or equivalent). The board also supports raw TCP/UDP socket connections for custom applications. The protocol selection is done in the I/O configuration—you enable the protocols you need and disable the rest to save memory. The firmware is field-upgradable; we can supply the latest version if needed.

Q: Can I use the NCID1C as a Modbus gateway?
Yes. The board can act as a Modbus TCP-to-RTU gateway—it receives Modbus TCP requests from the Ethernet port and forwards them to serial devices (RTUs) via the serial ports. It can also translate Modbus TCP to GE SRTP for HMI communication. However, the gateway function is limited to 16 concurrent connections—if you need more, you’d need a dedicated gateway (e.g., a ProSoft module). GE’s manual GEK-108512 has the full configuration procedure.

Q: The watchdog timer keeps resetting the board. What’s causing that?
The watchdog timer is designed to reset the board if it stops responding—typical cause is a software lockup (e.g., a protocol stack crash). The 1.5s timeout is the default, but you can increase it to 3s or 5s via the configuration. If it’s resetting frequently, check the serial ports for noise—we’ve seen noisy RS-232 lines cause the UART to generate interrupts that overwhelm the processor. Try disabling unused serial ports to see if the resets stop. If the watchdog is set too aggressively (e.g., 500ms) and the board is busy with heavy Ethernet traffic, it might reset erroneously. Set it to 3s and test.

Q: What’s the maximum number of simultaneous Ethernet connections?
The NCID1C supports up to 32 concurrent TCP connections across both ports—16 per port. That’s a significant increase from the older NCID, which supported only 8 total. In practice, a typical Mark VI configuration has 3-4 HMIs, 2-3 DCS connections, and maybe 2-3 Modbus clients—well within the 32 limit. If you’re using a single Ethernet port for both HMI and DCS traffic, you might approach the limit—spread the load across both ports.

Q: The Ethernet Link LED is on, but I can’t ping the board. What’s the first thing to check?
The IP address. The NCID1C stores its IP settings in flash memory. If the board was previously in a different rack with a different subnet, the IP won’t match your network. Use the serial console (RS-232 port 1, 9600 baud, 8N1) to connect and check the IP settings. The default IP is 192.168.1.200, but if that’s been changed, you’ll need to either use the console or reset the board to factory defaults (there’s a dip switch on the board—see GE manual for the procedure). If the IP is correct, the Ethernet cable might be bad—try a known-good cable.

Q: The serial port is showing garbage characters. What’s the most common cause?
Baud rate mismatch. The NCID1C and the connected device need to match exactly—baud, parity, data bits, stop bits. If any of those are mismatched, you’ll get garbled data. Use the serial console to check the port settings. Also, check the cable—RS-232 requires a null modem cable (crossed TX/RX) when connecting two DTE devices. If you’re using a straight-through cable, you’ll get no communication or garbage. We’ve seen this on many plants.

Q: Can I use the NCID1C for time synchronization?
Yes. The board supports SNTP (Simple Network Time Protocol) to synchronize its internal clock with a network time server. It can also act as an SNTP server for connected devices. The board’s clock is battery-backed (CR2032) and has a drift of about ±2 seconds per day—SNTP corrects that. If you’re using the board for time-stamped event logging, SNTP is essential. We’ve seen plants skip this and have event logs that are 5-10 minutes off from the DCS logs—makes root cause analysis a nightmare.

Q: The 9-pin D-sub pinout on the NCID1C is different from my old NCID. Can you provide the new pinout?
Yes. The -1C revision standardized on the following pinout for each serial port:

• Pin 2: TX (RS-232)
• Pin 3: RX (RS-232)
• Pin 5: GND
• Pin 7: RTS (for RS-485 direction control, if used)
• Pin 8: CTS
• RS-485: uses pins 2 and 3 (TX/RX) with a 120Ω terminator option (internal jumper)
  The older NCID used a different pinout—we strongly recommend checking the wiring before powering up. We can send you a pinout diagram with your order. If you’re using RS-485, you’ll need a 120Ω terminator at the ends of the bus—the NCID1C has an internal jumper for that.

Q: Does the NCID1C support fiber optic Ethernet?
No. The board only has copper RJ-45 Ethernet ports. For fiber optic connectivity, you’ll need an external media converter (e.g., a copper-to-fiber transceiver). Some plants use this for long-distance connections (up to 2km) between the turbine and the control room. The NCID1C’s Ethernet ports are 10/100Base-TX, which is copper only.

Q: What’s the firmware update procedure?
You’ll need GE’s Toolbox software and a serial cable (for the initial connection) or Ethernet (for the upload). The firmware file (typically a .bin file) is uploaded via TFTP. The board has a bootloader that listens on port 69 for new firmware. The update takes about 2-3 minutes. We recommend backing up the existing configuration before updating—the update doesn’t erase the config, but we’ve seen rare cases where it does. GE’s manual GEK-108532 has the full procedure. We can supply the firmware file if you don’t have it.

Q: What’s the lead time for a surplus NCID1C?
We keep 3-5 units in stock. Domestic: 2-3 business days ground, overnight if ordered by 2 PM EST. International: 5-7 days via DHL, with customs potentially adding 1-3 days. This board is subject to ITAR regulations because of its cryptographic capabilities (some protocols use encryption). If you’re outside the US, we’ll need an end-user certificate. For domestic orders, no license is required. We include a GE certificate of origin and commercial invoice with every shipment.

ABB V4550220-0100
ABB V4550220-0100
GE HE697RTM700B
SIEMENS 6SE7021-0TA61-Z G93