Overview
PSCL has a long history of supplying automation services and support for cement terminals, for both greenfield (installs in new facilities) and retrofit projects.
Our Automation specialists have been noticing a trend while at cement terminals. Many PLCs these terminals rely on have reached or exceeded their expected service life. We have identified a list of current and upcoming end-of-life hardware to help assess the risks that may be present on your site. Unaddressed aging hardware may become an issue or even cause loading to stop entirely. An investment into your process controls can save you from the comparatively higher costs of multiple days of lost time and sales when your PLC hardware fails. Downtime could be even longer if there is no backup to site programming or replacement hardware cannot be found.
It is difficult to identify exactly when the hardware will fail as these units have been known to continue working past their normal operating life span, but as the hardware ages the risk of failure is compounded with limited availability of legacy software and replacement parts.
Due to the risks, PSCL provides limited troubleshooting support for these identified PLCs and will not modify or change the existing programs due to the risk. For your site to remain reliable and supportable we highly recommend replacing end-of-life hardware with a PSCL-supplied control system.
Risk Levels
- High – High-risk items are PLCs that have reached their end of life and failure could lead to a major site failure. Part availability and software support is limited, amplifying the risk factor.
- Moderate – Moderate-risk items are PLCs that have reached their end of life and are no longer supported by the manufacturer. Part availability and software support is limited, amplifying the risk factor.
- Lower – Lowest-risk items are PLCs that are still supported by the manufacturer, but an end-of-life date has been announced. Parts may also be limited due to the age of the product.
Allen-Bradley Micrologix 1000, 1200 & 1500 – High Risk
The Micrologix 1000, 1200 and 1500 PLCs have become outdated and have been discontinued by Allen-Bradley. Replacement processors and components are no longer available from Allen-Bradley as of December 2021. These PLCs utilize battery backup memory. If the batteries are not replaced on a maintenance schedule and are allowed to deplete the program will be lost if there is a power failure.
PSCL highly recommends immediate replacement of these PLCs.
- Battery memory backup requires the memory batteries to be changed on a regular basis, otherwise the program may be lost in the event of a power failure/loss
- Supply chain of early-model components are now limited to refurbished items through third-party vendors
Allen-Bradley PLC 05 – High Risk
The Allen-Bradley PLC05 was introduced in 1986 and was one of the most common PLCs of its time. These PLCs have become obsolete and were discontinued by the manufacturer in 2018. Although the manufacturer has not discontinued the entire product line, various components and controllers have been removed from the manufacturer’s supply chain. Replacement or spare parts are becoming difficult to source, as components must now be found through grey or used markets.
- Product line introduced in 1986 and discontinued in June 2018
- Remote connectivity is limited with respect to new PLC communication standards and capability
- The PLC05 product line has exceeded the product service life of 20 years
- Supply chain of various components are now limited to refurbished items through third-party vendors
Allen-Bradley SLC 05 – Moderate Risk
The SLC Small Logic Controller – known as the SLC500 – was launched in 1990 and was the one of the most common PLCs utilized for a generation. Although the manufacturer has not discontinued the entire product line, various components and controllers have been removed from the manufacturer’s supply chain. These PLCs use battery backup memory. If the batteries are not replaced on a maintenance schedule and are allowed to deplete, then the program will be lost if there is a power failure.
- Product line introduced in 1990, many SLC05s in the field have exceeded a reliable product service life of 15–20 years.
- Battery memory backup requires the memory batteries to be changed on a regular basis, otherwise the program may be lost in the event of a power failure/loss.
- Remote connectivity is limited with respect to new PLC communication standards and capability.
- Supply chain of early model components is now limited to refurbished items available through third-party vendors.
Models
PSCL highly recommends immediate replacement of:
- SLC 5/01
- SLC 5/02
- SLC 5/03
- SLC 5/04
Modicon Quantum PLCs – Moderate Risk
The Modicon Quantum PLC series has been retired by the manufacturer, and its production was ceased in 2018. It is difficult to remotely connect to and support these PLCs, due to a requirement for varying software programs with different iterations of each. The discontinued hardware for these PLC product lines is becoming difficult to source as components must now be obtained through refurbishing vendors or resellers.
- Launched in the market in 1994 and discontinued in 2018, replacement parts are no longer available.
- Requires Windows 98/XP software to log onto and troubleshoot, and the newer versions require specialized legacy software.
- Reliable service life is ~15–20 years. After this time frame, the electrical equipment becomes more sensitive to power bumps/outages and may fail.
- Fewer vendors have the training or the software to provide support. PSCL does provide troubleshooting support, but we will not conduct program changes/edits due to the equipment failure risk.
Models
PSCL has identified the following models as end-of-life:
- M340 BMX342030
- M340 BMXP341000
- M340 BMXP342010
- M340 BMXP342020
- M580
- Momentum 171CCC7xxxx
- Momentum 171CCC9xxxx
- Momentum 171CCS7xxxx
- Premium TPCX57xxxx
- Premium TSXP57xxxx
- Quantum 140CPUxxxxx
Allen-Bradley Micrologix 1100 – Lower Risk
As of December 2021, the Micrologix 1100 series is no longer supplied by Allen-Bradley but will be supported for another five years. PSCL can connect and perform edits, changes, and upgrades to these PLCs for the time being. PSCL recommends that the site evaluate their stock of replacement components in the short term and schedule an upgrade in the next 3–5 years.
- Micrologix 1100 – product line introduced in 2005, discontinued in 2022.
- Reliable service life is ~15–20 years. After this time frame, the electrical equipment becomes more sensitive to power bumps/outages and may fail.
- Can easily be upgraded to ML1400 PLC (size permitting).