DS200RTBAG1AEB | GE Mark V Relay Termination Board

Description

Product Introduction

The DS200RTBAG1AEB is a high-current relay output termination board for GE’s Mark V DS200 series, used in Speedtronic turbine control systems. It provides 16 independent Form C relay outputs rated for 10 A continuous—double the current capacity of the standard RTBAG1A.

The “AEB” suffix indicates the high-power variant of the RTBA family. Compared to the standard RTBAG1A (5 A rating), the AEB revision uses larger relay contacts (10 A), wider PCB traces (6 mm on power paths), bifurcated contacts for reliability, and screw-type fixed terminals (no removable blocks) to handle higher currents. This board is designed for direct switching of motor starters, large solenoid valves, heater contactors, and pump controls.

Key Technical Specifications

Key Selling Points & Differentiators

• 10 A continuous contact rating – Double the standard RTBAG1A (5 A). Switch motor starters (1 HP at 120 VAC), large solenoids, and heater contactors directly. No external interposing relays needed for most applications.
• Bifurcated (twin) contacts – Each contact has two parallel touching surfaces. Reduces contact resistance by 50% and provides redundancy. If one surface fails, the other maintains the circuit. Standard relays use single contacts.
• External coil power option – Standard RTBAG1A draws 240 mA (16 x 15 mA) from the backplane. The AEB draws 480 mA (16 x 30 mA) at 24 VDC. For heavily loaded backplanes, move the jumper to use an external 24 VDC supply. Relays still controlled by the Mark V output module; only coil power comes from external source.
• Dual LED status per channel – Red LED = coil energized (command from output module). Green LED = contact closed AND field voltage present (requires external field power sense). Green LED helps verify that the contact actually closed and field power is available—not just the coil.
• RCD snubber across coil – Standard flyback diode plus 470 nF capacitor and 47Ω resistor. Dramatically reduces EMI from coil switching. Prevents false triggers on nearby analog inputs. Tested to EN 61000-4-4 (burst immunity) at 4 kV.
• Wider PCB traces (6 mm) on power paths – Standard board uses 3 mm traces. AEB uses 6 mm traces with 4 oz copper. Temperature rise at 10 A: 25°C versus 50°C on standard board.
• QC includes 10 A load test on all 16 relays for 24 hours – Every relay runs at 10 A resistive, 30 VDC for 24 hours continuous. Contact resistance measured before and after (<50 mΩ initial, <100 mΩ final). Thermal imaging verifies no hot spot >85°C.
• 2-year warranty – Covers contact welding, coil failure, LED failure, or any manufacturing defect. Includes high-current switching duty.

Frequently Asked Questions (FAQ)

Q: What’s the difference between RTBAG1A, RTBAG1AEB, and RTBAG1ABB?

The AEB is for high-power switching. Do not use it for low-level signals (<100 mA)—the contacts require minimum load for self-cleaning.

Q: Can I replace a standard RTBAG1A with an AEB without changing my I/O module or wiring?
A: Yes—electrically and logically, yes. The pinout and ribbon cable are identical. However, the AEB uses fixed screw terminals, not removable blocks. Your existing wires from the RTBAG1A (removable blocks) will need to be re-landed onto the fixed terminals. The terminal numbering (1–16, C/NO/NC) is the same. Allow 2–3 hours for re-termination.

Q: Why does the AEB need an external coil power option?
A: The larger relays require 30 mA each versus 15 mA on standard. 16 relays = 480 mA at 24 VDC. Some Mark V backplanes have limited 24 VDC capacity (typically 1–2 A total for all modules). If your backplane already supplies CPU, I/O modules, and other boards, adding 480 mA may exceed capacity. Use the jumper to power coils from an external 24 VDC supply (2 A minimum). The Mark V output module still provides the control signal (opto-isolated).

Q: How do I know if I need external coil power?
A: Calculate your backplane 24 VDC load. List all modules: CPU (DS200CPCAG) draws 500 mA, each I/O module 100–300 mA, communication boards 200–400 mA. Add 480 mA for the AEB if using backplane power. If total exceeds the power supply rating (typically 5 A for DS200PCCAG series), use external power. We provide a load calculation worksheet with each board.

Q: The green LED (contact closed) does not light even though the relay clicks. Why?
A: The green LED requires field power on the Common (C) terminal. It senses voltage between C and NO when the relay is energized. Connect field power (24 VDC or 120 VAC) to the C terminal. The LED works with AC or DC from 12 V to 250 V. If the LED still does not light, the contact may be welded open or the field power missing. Measure voltage across C and NO with a meter.

Q: Can I use this board for 240 VAC at 10 A?
A: Yes. The contacts are rated 10 A @ 250 VAC resistive (heaters, lights). For inductive loads (motors, solenoids) at 240 VAC, derate to 5 A. The inrush current of an AC motor can be 6–8x running current. A 1 HP motor at 240 VAC draws 4 A running but 25 A inrush. The AEB contacts will weld on the first start. Use an external motor starter (contactor) for any motor above 1/4 HP.

Q: What is the derating curve for temperature?
A: At 60°C ambient: 7 A resistive maximum. At 70°C ambient: 5 A maximum. Above 70°C: do not operate (coil may not pull in reliably). The board has a built-in thermistor (accessible via test points) to monitor PCB temperature. If temperature exceeds 75°C, the yellow warning LED on the board edge lights. We recommend forced air cooling if operating above 50°C at full load.

Q: Can I replace individual relays on the AEB?
A: Yes, but with difficulty. The relays are through-hole soldered with 8 pins on a 2.5 mm grid. Desoldering requires a vacuum desoldering station. We offer relay replacement service (25 per relay + return shipping). The AEB relays are larger and more expensive than standard RTBA relays. We also sell bare relays (part RELAY-HP-10A, 18 each) for in-house repair.

Q: What QC tests are specific to the AEB revision?
A: Ten tests, all documented with thermal images:

1. Visual: 20x magnification of power traces (6 mm width, 4 oz copper).
2. Coil resistance: 800Ω ±3% at 25°C (30 mA at 24 VDC).
3. Coil current: 30 mA ±3 mA from backplane power; same from external supply.
4. Contact resistance: Four-wire measurement at 1 A (not 100 mA—higher current for power relay). <30 mΩ initial.
5. Isolation: Coil-to-contacts: 3000 VAC for 5 seconds. Contact-to-contact: 1800 VAC.
6. Operate test: Cycle each relay 500 times at 2 Hz. Operate time <20 ms, release <12 ms.
7. Load test (all 16 relays): 10 A resistive at 30 VDC, 24 hours continuous. Contact resistance measured at 0, 1, 2, 4, 8, 12, 24 hours. Final <100 mΩ.
8. Inductive load test (sample of 4 relays): 5 A at 30 VDC, L/R = 40 ms, 25,000 cycles. No contact welding.
9. External coil power test: Jumper set to external supply, verify coils operate correctly, backplane draws <20 mA (only control current).
10. Thermal imaging: Full load (10 A on all 16 relays) for 2 hours. Hot spots <85°C. Thermal image included in QC report.
11. Green LED sense test: Apply 24 VDC and 120 VAC to C terminal, verify LED illuminates when relay energized.

Q: What shipping protection for this heavy board?
A: The AEB weighs 2.2 kg (4.9 lbs). Custom packaging: anti-static bag, ESD foam cradle with cutouts for relays and terminal blocks, double-wall box with “HEAVY,” “FRAGILE,” and “DO NOT STACK” labels. Shock indicator on outside. The fixed screw terminals are covered with a formed plastic cap to prevent bending. Each board ships individually. Thermal pad kit (for mounting to metal backplane for heat sinking) included in separate bag.

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