Table of Contents

• 1. Mechanical Installation
• 2. Sensor Wiring
• 3. Bus Power and Loop Wiring
• 4. Dual-Channel Configuration
• 5. Cold Junction Compensation Setup
• 6. Field Calibration Procedures
• 7. LCD and Local Operation
• 8. Explosion-Proof Installation Requirements
• 9. Startup and Verification Checklist
• 10. Troubleshooting Quick Reference

1. Mechanical Installation

The NCS-TT105 offers three mounting bracket options. Select based on your installation location and pipe diameter.

1.1 Mounting Bracket Types

1.2 Installation Steps

Step 1: Secure the transmitter to the bracket

Use the four M4 bolts (provided) to attach the transmitter body to the bracket. Torque to standard industrial specification.

Step 2: Mount to pipe or wall

• Tube mounting: Feed U-bolt around the pipe, position the bracket, and tighten nuts evenly.
• Plate mounting: Use M10 bolts (not included) to secure through the panel.

2. Sensor Wiring

The NCS-TT105 terminal board is located behind the rear cover. Recommended wire gauge: 0.5 ~ 2.5 mm² (AWG 20 ~ 14).

2.1 RTD Wiring Diagrams

2-wire RTD wiring:

(1)---[RTD]---(2)
      |       |
(3)---+       +---(4)
(Jumper 1-3 and 2-4)

3-wire RTD wiring:

(1)---[RTD]---(2)
      |       |
(3)---+       +---(4)
(Jumper 1-3)

4-wire RTD wiring:

(1)---[RTD]---(2)
(3)-----------(4)
(No jumpers)

3. Bus Power and Loop Wiring

Warning: Do not connect the signal wire to the T+ test terminal. This will damage the protection diodes. If diodes are accidentally burnt, short circuit the T+ and – terminals as an emergency workaround.

3.4 LCD Diagnostic Indicators

4. Dual-Channel Configuration

4.2 PV Calculation Logic (SENSOR_MEAS_TYPE)

When SENSOR_MEAS_TYPE is configured for redundancy (193), the transmitter uses a state-machine logic: if SV_1 status becomes ‘Bad’ or ‘Uncertain’, the PV automatically switches to SV_2 to maintain process uptime.

5. Cold Junction Compensation Setup

CJC accuracy is critical for thermocouples. For precision applications, use RJ_TYPE = Sensor 2 with a Pt100 RTD on channel 2 to measure the terminal temperature more accurately than the internal sensor.

6. Field Calibration Procedures

Field calibration ensures the transmitter compensates for site-specific variables like lead wire resistance and environmental conditions.

6.1 Two-Wire RTD Zero Calibration (Fun 26)

Note: You must short the leads at the sensor end (not the transmitter terminals) to accurately compensate for the lead wire resistance.

1. Short the RTD leads together at the sensor.
2. Navigate to Fun 26 on the LCD using the [Z] and [S] keys.
3. Press [M] to enter, then press [S] to start calibration.
4. When “OK” appears, the lead resistance is zeroed out.

6.2 HART Zero and Span Trim (HartMPT)

For high-precision loops, use the HartMPT software to align the 4-20mA output with your master ammeter:

• Go to Calibration → Output Trim.
• Connect a precision multimeter in the loop.
• Input the actual mA reading into the software to adjust the D/A converter.

7. LCD and Local Operation

The NCS-TT105 supports full local configuration via three magnetic buttons (Z, S, M). No communicator is required for basic setup.

• Fun 22
• Fun 23
• Fun 25
• Fun 26

8. Explosion-Proof Installation Requirements

8.1 Flameproof (Ex d) Installation

• Ensure the enclosure cover is tightened until there is no gap.
• Use certified Ex d cable glands with at least 5 threads engaged.
• Do not open the cover in a hazardous area when the power is on.

8.2 Intrinsically Safe (Ex ia) Installation

• Must be powered through a certified safety barrier (e.g., V_o ≤ 30V, I_o ≤ 120mA).
• Total loop capacitance and inductance must not exceed barrier limits.

9. Startup and Verification Checklist

Before leaving the site, verify the following:

• [ ] Physical: All covers tightened, cable glands sealed with weatherproofing.
• [ ] Configuration: SENSOR_TYPE matches the installed sensor.
• [ ] Loop Power: Voltage at terminals is between 11.5V and 45V DC.
• [ ] Calibration: 4mA and 20mA points align with the DCS range.

10. Troubleshooting Quick Reference