2-Channel Dual EGT Digital DPG-XR Pyrometer Gauge + Probe Kit - Diesel Commercial Industrial Series DP

The DPG-XR Diesel Series kit pairs a dual-channel digital pyrometer gauge with two diesel-duty Type K EGT probes, providing the components required to monitor exhaust gas temperature at two critical measurement points. This configuration is commonly used for monitoring pre- and post-turbo temperatures, dual exhaust banks, or multiple turbocharger stages in diesel applications.

The gauge mounts in a standard 2-1/16" (52 mm) panel cutout, while the probes install using 1/8"-27 NPT compression fittings into welded or threaded bung ports.

Kit Contents

• DPG-XR Series 2-Channel Digital Pyrometer Gauge (1)

• Diesel Commercial/Industrial EGT Probes, 3/16" diameter (2)

• 316 SS adjustable compression fittings, 1/8"-27 NPT male thread (2)

• Thermocouple connectors (2)

• Weld bungs — optional, selected at checkout (2 if added)

Why Diesel EGT Monitoring Is Different

In diesel engines, EGT monitoring functions primarily as a protection tool rather than a tuning reference. Under heavy load, towing, or modified fueling conditions, exhaust temperatures can approach levels that lead to turbine damage, piston failure, or exhaust component distortion if left unchecked.

The key diagnostic question is how close the system is operating to its thermal limits. The DPG-XR provides a primary real-time indication of exhaust temperature, allowing operators to manage load and fueling before critical limits are exceeded.components.

Two-Channel Monitoring Configurations

With two input channels, several common monitoring strategies are supported:

• Pre- and post-turbo measurement: Provides insight into turbocharger performance by comparing temperature before and after the turbine. 
• Dual exhaust banks: Allows monitoring of temperature differences between engine banks. 
• Compound turbo systems: Enables independent monitoring of multiple turbo stages. 
• Pre-DPF monitoring: Supports observation of temperatures entering emissions components.

Diesel-Duty EGT Probe Construction

The included probes are designed specifically for diesel exhaust environments, which involve higher particulate levels and more aggressive chemical exposure than gasoline applications.

• Inconel 600 sheath: Provides corrosion resistance in high-temperature, sulfur-containing exhaust environments and maintains structural integrity under sustained heat. 
• Ungrounded (sheathed) junction: Helps minimize ground loop interference and protects the sensing junction from contamination and mechanical damage. 
• FEP-insulated cable with stainless over-braid: Offers improved heat resistance and mechanical protection for routing in engine bays and along frame rails. 

The probes have a typical response time of approximately 150 ms, which is well suited for diesel applications where temperature changes occur over longer time scales.

Probe Installation: Bung, Compression Fitting, and Positioning

Bung Selection

The probe mounts via a 1/8"-27 NPT compression fitting threaded into a bung port welded to the exhaust pipe. Bung material selection matters:

If your exhaust pipe doesn't have an existing bung port, the optional Drill & Tap Kit for 1/8" NPT thread (sold separately) provides everything needed to create a clean threaded port without removing the exhaust system. Weld bungs require welding; if welding capability isn't available, the direct-weld compression bung can be TIG or MIG welded by a local shop with no prior machining.

Probe Insertion Depth

The maximum tip insertion depth is 1.1" (27.94mm). The probe tip should be positioned in the center of the exhaust gas flow path — not so shallow that it reads near-wall temperatures, and not so deep that the sheath contacts the opposite pipe wall. On exhaust pipes 1.5" diameter and larger, centering the tip is straightforward. On smaller-diameter pipes (some 2-stroke diesels or secondary cylinders), verify clearance before fully tightening the compression fitting.

Probe placement on a turbocharged diesel is typically in the exhaust manifold runner, upstream of the turbine inlet. This location reads the highest temperature the turbine wheel will see and is the most useful protection measurement. Post-turbo placement is viable for compound turbo or inter-stage monitoring but reads temperatures 200–400°F lower than pre-turbo on a healthy system.

Cable Routing and Cable Length Selection

This kit is available with 6-foot, 12-foot, or 25-foot probe cables. Selecting the right length avoids field splicing, which introduces potential signal degradation and junction voltage errors in thermocouple circuits. Measure the routing path from bung location to gauge — accounting for slack at both ends and any routing around hot exhaust components — before selecting cable length.

Key routing considerations: keep the cable away from exhaust pipe surfaces hotter than the FEP jacket's continuous temperature rating; use the included stainless braid to protect against abrasion at any tight bends or clamp points; and avoid routing through areas with fuel or oil accumulation that could degrade the jacket over time. The compression fitting provides a gas-tight seal at the exhaust pipe; verify the fitting is fully tightened to prevent exhaust gas leaks that could affect temperature accuracy and present a CO hazard.

DPG-XR Gauge: Features and Operation

The DPG-XR is a compact 2-1/16" digital pyrometer designed for both 12V and 24V systems.

Key features include:

• 4-digit LED display with user-selectable colors 
• Dual-channel input, displayed sequentially 
• Peak hold function for capturing maximum temperature values 
• Programmable high-temperature alarm with internal 2-amp relay output 
• User-adjustable temperature offset per channel
• Support for Type K, J, T, and E thermocouples 

The display updates in real time and cycles between channels, making it well suited for applications where each measurement point is monitored sequentially.

Electrical Integration

The gauge operates on 9–28 VDC, making it compatible with both automotive and commercial electrical systems. With a nominal current draw of approximately 50 mA, it can be powered from standard accessory circuits.

The integrated 2-amp alarm relay allows direct connection to warning indicators or control systems, providing advance warning to allow corrective action when temperature limits are approached.