Article

Water in Junction Box? PIE Finds 4 to 20 Milliamp Loop Problems

Junction Box

Help! We have water in junction box on control loop 7.

Water in junction box…how many times have you seen this in your plant? Where does the water come from? Here are some possible causes…and an easy way to find out if you have hidden problems in YOUR junction boxes.

Leaky conduits

Over time heating and cooling of conduits can cause expansion and contraction of joints causing gaps where liquids can get in. Seals, gaskets and O-rings can deteriorate over time, especially when they are dried out or attacked by process chemicals or fumes.

Condensation in conduits

Warm air is capable of holding more moisture than cold air. When air is trapped in a warm conduit, and the conduit is cooled, some of the moisture will deposit as water drops on the walls of the conduit. As the process is repeated more drops form and eventually flow along the conduit and into a junction box. Conduits that are exposed to the sun, running next to a hot process, or are exposed to freezing temperatures are especially susceptible to condensation.

Inspections to look for water in junction box

In some facilities, junction boxes are inspected on a regular basis to check for moisture and corrosion. While this is considered preventative maintenance each time the junction box is opened there is a chance of introducing moisture or contaminants and taking the risk of striping screws, cross threading covers, or tearing gaskets. Loose covers can also cause problems down the road.

Floods

Whether caused by accidents or Mother Nature there are times that process areas get flooded. Prolonged exposure to standing water or process chemicals will seep through small holes or cracks. This is a major reason to check for water in junction box.

Rewiring

As replacement or additional wires are pulled through a conduit plumbers putty and seals can get displaced or damaged.

Do you have hidden problems in your process control loops?

Leak Detection

Find these problems caused by moisture or corrosion in junction boxes only by using PIE calibrators with patented current leak detection.

PIE Calibrators with built-in ground leak detection

mA Loop Diagnostic Calibrator – PIE 334Plus

4-20 milliamp loop calibrator with current leak detection $1,370.00