To help offset the financial effects of Covid-19, your company’s corporate office installed a new “tough on cost” controller last summer. A planned expansion was already in the works, and the new production line was delivered. However, instead of letting the plant engineer use the same industrial services firm the plant’s been using for the past 15 years, the controller insisted the installation be put out for bid and awarded to the lowest bidder.

The job ran past schedule by two weeks, partly because this firm didn’t work on it every day from start to finish. The first order is supposed to ship tomorrow. The operators can’t get the line moving and the message “Protection Mode Activated” appears on the operator screen.

The machine builder can’t send someone for three days. Your boss tagged you to fix this. What should you do?

First, find the list of protection modes and/or protection mode triggers for that control system. Methodically go through each one. Contact the manufacturer if you do not have the information in the documentation the machine builder sent over. Some typical protection mode triggers include:

• High ground impedance. Connecting to chassis instead of ground connections can cause this.
• Neutral ground bond. Ensure neutrals go to neutral terminals, grounds to ground terminals.
• Short or low impedance at input terminals. Check for stray wire strands.
• Wrong polarity at input or output terminals. Visually inspect; correct as needed.

You and the plant engineer should talk with the controller about the value of relationships with good contractors. The “savings” from that low bid were wiped out several times over by the costs of poor performance and poor customer service.