Wiring practices

Wiring practices should meet the manufacturers recommendations and NEC requirements. Deviations should have safety review and analysis. 

Additional considerations for electronic or programmable electronic SIS include  

Electronic and programmable electronic logic solvers use internal low-level logic signals. Use of low-level logic outside the shielded controller cabinet may be inappropriate. 

Electronic and programmable electronic logic solvers may require a more restrictive wiring approach because inductive or capacitive coupling may falsely turn on inputs. 

No reproduction or networking permitted without license from IH  

---

The derivation for the gas amplification does not take into account the effect of the drifting positive ions in a proportional counter. Indeed, due to the narrow amplification region, around the anode wire, practically all the charges are created in a very small volume. These ions drift rather slowly away from the wire. They tend to reduce the electric field around the wire. If a second photon is detected at the same position on the wire, the field and consequently, the gas amplification will be lower. Since the density of the positive ions, in the anode-cathode gap increases... 

Several means are available to prevent individuals from coming into contact with electricity in addition to exclusbn of unqualified personnel from space, as mentioned in the introduction to this section. These include insulation, grounding, good wiring practices, and mechanical devices. Before addressing these latter options, it might be well to briefly discuss the concept of a qualified person. 

Electronic and PE logic solvers typically are more sensitive to electrical noise (e.g., radio frequency interference or electromagnetic interference), consequently, shielding, good wiring practices, and proper grounding should be utilized. 

Storage and installation and wiring practice to follow manufacturer s instructions. 

Digital outputs are frequently used for actuation of valves, LEDs, etc. An LED being a simple apparatus does not require entity approval whereas a valve actuator such as a solenoid valve needs entity approval. Positive DC IS barriers are used. In most cases these barriers are rated for 24 VDC. Rj is calculated from the selected device. Typical values for LEDs and solenoid valves can be 480 and 350 Q [34]. System configuration is similar to what has been shown in Fig. X/3.7.5-1, only +4—20 mA will be replaced by +24 VDC via the contact. The return line will be grounded at the DCS as shown. The IS barrier will be grounded. With discussions on IS barrier for various I/Os concluded we will now move on to wiring practices. 

Electric motor wiring requirements go beyond simple connections to the correct motor lead. The NEC describes in detail many characteristics of proper wiring practices. References such as McPartland and McPartland (1990) provide... 

Good wiring practices are essential to ensuring desired SIS availability is achieved. Following is a list of wiring practices that were implemented in this SIS ... 

If you are not familiar with standard wiring practice, don t attempt this part of the project yourself. Consult a professional electrician. Insure that all wiring conforms to your local code. In this project, the white wire is neutral, the black wire is the hot wire and the bare copper wire is ground. For safety reasons, it is very important that the entire machine be grounded. The machine operates on a 20 amp circuit and as a safety precaution, I suggest plugging the machine into a GFI outlet. GFl stands for Ground Fault Interrupter. This type of outlet is very sensitive to electrical shorts and will immediately shut the circuit down if one occurs. 

---