Bid Package 08 North Well Field - Garney Construction

6) High CPU temperature
7) Scan time overrun
8) Module failure
9. Control of Programs:
a. Protect access to PLC program loading with locked, key operated selector switches.
10. Effects of Failure:
a. PLC system shall incorporate safe responses to the following failure effects:
1) Power losses, interruptions, excursions, dips, and transients.
2) Loss or corruption of memory
3) Information transfer corruption or loss
4) "Fail on" or "Fail off" of inputs or outputs
5) Unreadable signals
6) Addressing errors
7) Processor faults
11. Design PLC system with high noise immunity to prevent occurrence of false logic signals
resulting from switching transients, relay and circuit breaker noise or conducted and
radiated radio frequency interference.
12. Incorporate noise suppression and inductive load suppression design into input, output,
and logic modules
13. Operator Intervention:
a. Logic system failure shall not preclude proper operator intervention
b. Safety shutdown of equipment or a system shall require manual operator
intervention before the equipment or system operation may be reestablished.
2.02 COMPONENTS
A. PLC System Central Processor Unit (CPU):
1. Completely solid state CPU designed to provide:
a. Digital relay logic
b. Analog loop control
c. Other required control functions:
1) Counting
2) Floating point math computations
3) Timing
2. To provide communications with other control systems and man-machine interfaces as
specified.
3. To use electrical ladder diagram style programming for discrete logic applications.
4. Memory:
a. Battery-backed RAM
5. Memory battery backup shall be capable of 60 days memory retention with fresh
battery.
a. Provide visual indication of battery status and alarm low battery voltage.
Supervisory Control and Data Acquisition (SCADA) System 40 90 02-15
CMD11269 – Ward County Transmission System Expansion – Contract C – Above Slab TPS, OPS, and WPS