ISA CAP case studies
ISA CAP · Put your knowledge to work in context.
The ISA Certified Automation Professional (CAP) is a professional credential administered by the International Society of Automation for practitioners who specify, design, integrate, and maintain industrial automation and control systems. Qualification is based on a combination of technical education and documented automation work experience. The ISA CAP case studies are 5 cases and about 5,310 words.
1Reflux Drum Level Loop: Stiction or Tuning?
A depropanizer reflux drum (1.8 m ID, 2.4 m tangent-to-tangent) splits reflux from distillate with a level controller. At normal rates the drum's residence time is about 2.5 minutes, so the level behaves as a fast integrator.
1,051 words, about 5 min2Extending a SIL 2 Proof Test Interval and Running a 30-Day Bypass
A naphtha hydrotreater's high-pressure trip is credited as SIL 2 in the site LOPA. The SIF is 1oo2 on two pressure transmitters into a safety PLC, de-energize-to-trip, with a single 1oo1 trip valve in the feed line.
1,166 words, about 6 min3Month 8 on a Lump-Sum Water Plant Automation Contract
A systems integrator is 8 months into a 14-month, 4.2M lump-sum contract to automate a 45 MGD water reclamation plant: redundant PLCs, 14 MCCs, a new SCADA, and a 3,800-point I/O database. Month-8 status: planned value 57% of BAC; earned value 48%; actual cost 2.31M.
1,037 words, about 5 min4A Flat Control Network, a Dual-Homed Historian, and 40 Seconds of Timestamp Drift
A consumer-goods plant has a DCS in the process area and a separate PLC on the packaging line. Both sit on one flat Layer-2 network of about 420 nodes on a single /16 subnet.
1,060 words, about 5 min5Steam Flow Reads Half of the Heat Balance at Part Load
A 12-inch steam header feeds a reboiler. Flow is measured with an orifice plate and a DP transmitter ranged 0–150 inH₂O, which the orifice datasheet says corresponds to 45,000 lb/h at design conditions (250 psig, 500 °F).
996 words, about 5 min