DS3800XTES1A1A | GE OEM Mark VIe Terminal Board

Description

Product Introduction

The DS3800XTES1A1A is the enhanced, coated revision of GE’s universal thermocouple input board. That “1A1A” suffix tells you this is a later production run with a 24-bit sigma-delta ADC instead of the 16-bit converter on the base XTES—that extra resolution translates to about 0.05°C of measurement noise versus 0.2°C on the older boards. The coating is acrylic, which adds protection against humidity and dust without trapping too much heat.

This board is the top-tier TC input option for Mark VIe systems—it supports seven thermocouple types per channel, includes self-calibrating cold junction compensation, and offers the best accuracy of any GE TC board in this form factor. You’ll find it in applications where measurement precision matters, like steam turbine efficiency monitoring or compressor performance tracking. The conformal coating makes it suitable for cabinets that aren’t fully climate-controlled. Typical buyers are engineers doing precision thermal monitoring or upgrading from fixed-type boards to simplify spares management.

Key Technical Specifications

Compatible Replacement Models

Frequently Asked Questions (FAQ)

Q: Can I hot-swap this board?

No. The Mark VIe backplane does not support live insertion. Power down the entire I/O pack before removal. The 24-bit ADC is sensitive—we’ve seen hot-swap attempts corrupt the self-calibration constants, requiring a factory reset to recover.

Q: How is the 1A1A different from the base XTES?

Three upgrades:

• ADC: The 1A1A uses a 24-bit sigma-delta converter (versus 16-bit on the base XTES). That’s 256 times the resolution, which translates to lower noise and better small-signal accuracy. In practice, the noise floor drops from about 0.2°C to 0.05°C.
• Self-calibration: The 1A1A has an improved self-calibration routine that compensates for ADC offset and gain drift over temperature. The base XTES requires manual calibration.
• Coating: The “A” suffix (at the end) indicates acrylic conformal coating. The base XTES has no coating.

The TC type support and software interface are identical. The power draw is slightly higher (1.5A vs. 1.4A) due to the more complex ADC.

Q: What thermocouple types does this board support?

All standard types: K, T, J, N, E, S, R. It does not support Type B (high-temperature platinum-rhodium) or Type C (tungsten-rhenium). If you have those, you’d need external signal conditioners.

Q: How do I configure the TC type per channel?

Through ToolboxST. Each channel has a drop-down menu where you select the TC type. The board’s firmware then sets the appropriate gain and linearization constants. Unlike the base XTES, the 1A1A version retains the configuration in non-volatile memory—it survives a power cycle. We recommend configuring all channels before installation, but you can change them later.

Q: How do you test this board before shipping?

We run an 8-step test with multiple TC types and extra attention to ADC accuracy:

• Visual inspection: Check for cracked connectors, burnt traces, swollen capacitors. Inspect the coating for uniformity.
• ESD check: Insulation resistance between channels and chassis ground >10MΩ.
• Power-up: Apply +5V DC, measure current draw (1.5A ±10%).
• Communication handshake: Simulate backplane connection, verify board ID and firmware revision.
• Self-calibration: Power-up the board and verify the self-calibration completes with no errors. We check the calibration flags in the status register.
• CJC verification: Measure the board’s internal temperature via reference diodes against a calibrated thermistor—must match within ±0.3°C.
• TC simulation: Inject microvolt signals for Type K (0°C, 100°C, 500°C), Type J (0°C, 200°C, 400°C), and Type S (500°C, 1000°C). Verify accuracy within ±0.05% of reading ±0.3°C on all channels. We use a Fluke 714 calibrator with 0.01% accuracy.
• 24-hour soak: Run at 50°C ambient with all channels simulating 100°C (Type K). Log drift—failure threshold is ±0.3°C deviation.

We reject about 3% of these boards—the 24-bit ADC is sensitive to thermal drift, and some units fail the soak test.

Q: What’s the most common failure on this board?

Three things specific to the enhanced ADC:

• ADC reference drift: The internal voltage reference can drift with temperature, causing offset errors. The self-calibration corrects for this, but if the reference is far out of spec, the calibration fails. We see this on about 5% of refurbished units.
• CJC diode aging: The cold junction reference diodes drift with age. We replace them on about 10% of refurbished units.
• Coating-related heat: The acrylic coating traps a little heat—about 1-2°C at the ADC. The board’s calibration accounts for this, but if your cabinet exceeds 55°C, the ADC can drift. Keep your cabinet under 50°C for best accuracy.

Q: What’s the accuracy difference between the XTES and XTES1A1A?

The base XTES is ±0.05% of reading ±0.5°C. The 1A1A is ±0.05% of reading ±0.3°C—a meaningful improvement for precision applications.

Q: My analog inputs show 0.5°C noise. Will this board help?

Yes. The 24-bit ADC on the 1A1A has about 4x lower noise than the 16-bit ADC on the base XTES. If you’re seeing 0.5°C noise on a fixed-type board, the XTES1A1A will likely reduce it to 0.1-0.2°C. The digital filtering (software-selectable) can also smooth out noise at the cost of slower response time.

Q: What are the digital filtering options?

The board provides software-selectable filtering in ToolboxST:

• No filtering: Fastest response (100ms update), highest noise.
• 50Hz/60Hz rejection: Notch filter for power line noise.
• Low-pass: 1-10Hz cutoff for smooth readings.

We recommend 50Hz/60Hz rejection for most applications—it removes common mode noise without slowing response too much.

Q: Are there counterfeit versions of this board?

Yes, and the ADC is the giveaway. Genuine boards use a specific 24-bit sigma-delta converter (typically a Texas Instruments ADS1248 or similar). Counterfeits use cheaper 16-bit ADCs—they’ll read values but with lower accuracy and more noise. Also check:

• Reference resistors: Genuine boards use 0.05% precision resistors for the CJC reference. Counterfeits use 1% resistors.
• Coating: Genuine coating is uniform and matte. Fakes use cheaper lacquer.
• Label: Genuine—matte finish, greenish barcode. Fakes—glossy.

We trace stock to decommissioned assets. If buying elsewhere, demand photos of the component side and serial sticker, especially a close-up of the ADC chip.

Q: What’s your warranty?

1-year against functional defects. For the XTES1A1A, we also guarantee the ADC accuracy for the warranty period—if it drifts out of spec, we’ll recalibrate or replace it free of charge.

Q: What’s the lead time?

We typically carry 2-4 units. Orders before 2 PM EST ship within 1-2 business days after testing. The 24-hour soak is mandatory—we won’t skip it. Expedited shipping available with waiver. For precision temperature monitoring, we strongly recommend waiting for the full test cycle—the 24-bit ADC only shows thermal drift after hours of operation.

ABB REF615C-D
B&R CP260 3CP260.60-1
A-B 2711-B5A1/F