Tim Williams

Thermal Systems Control Tech Assoc Tucson AZ Description The Association of Universities for Research in Astronomy, Inc. (AURA) operates several observatory centers (including the National Optical Astronomy Observatory, the National Solar Observatory, Large Synoptic Survey Telescope and the Gemini Observatory) in the United States and Chile under a cooperative agreement with the National Science Foundation. The National Solar Observatory (NSO) Advanced Technology Solar Telescope (ATST) Project has an immediate opening for a Thermal Systems Control Technical Associate to provide support in the design and development of the ATST Project and the associated thermal systems. Initial development work will be done in Tucson, Arizona, while future installation, integration and testing will require relocation to Maui, Hawaii. NSO offers an excellent compensation/benefit package. The ideal candidate will work closely with the thermal systems engineer in implementing the automation and control of the facility thermal systems through process control element, PLC/PAC, HMI, and power & energy management system programming, debugging, assembly, installation, calibration, and integration. Additional tasks will be assigned in support of other systems as the ATST Project develops. ESSENTIAL FUNCTIONS: •Performs technical support activities, at an experienced level, including PLC/PAC/DCS programming and process controls installation, some project planning, and control and data analysis, as required. •Assists in solving design problems as required, achieving assigned project objectives. •Solves coordination problems of a technical nature directly or in conjunction with other members of a project team. •Assists other technical support personnel as necessary. •Recommends, and assists in development of, changes to existing designs and manufacturing procedures if appropriate. •Responsible for compliance with technical requirements and approved time schedules of assigned work. •Cooperates and coordinates closely with representatives of the major instrumentation and scientific divisions, and others involved with the assigned technical problem. •Monitors and reports results of activities and notes unusual situations. •Makes recommendations as to parts, materials, tools, and techniques to be used on a project. •Builds, assembles, modifies, repairs, troubleshoots and maintains equipment for a project. •Responsible for compliance with applicable safety standards and for safety of operations in areas under purview and reporting unsafe conditions and practices. •Prepares technical documentation for use by technicians, operators, engineers, and scientific staff. Requirements Minimum qualifications: Associate degree or military schools in engineering technology or related technical field and at least five years of technical experience. A bachelor’s degree in engineering may be acceptable in lieu of the experience requirement. Qualifications: •Minimum five years of broadly diversified experience in technology or engineering support. Associate degree, military schools, or college level courses in engineering or science, required. A bachelor’s degree in engineering may be acceptable in lieu of experience requirement. •Ability to resolve technical problems by application of engineering and physics principles relevant to project requirements in process control, mechanical technology, electronics, design drafting, optics, computer applications, and/or instrumentation. •Ability to speak and write effectively, including preparation and presentation of reports. Required skills: •Recent experience in process control system programming using function block programming including PID loop controls, cascade controls, multi-controller to final control element applications, feed forward, function generator configurations. •Working with screen development, graphics standards and management, dynamic graphic element configuration for process controls (faceplates for PID’s, motor controls, valve controls, dynamic equipment status graphics, alarm management and trending in HMI applications), and data historian configuration. •Process sensor and instrumentation installation, calibration, and troubleshooting skills are essential. •Applicant must be able to read and create electrical, mechanical, P&ID drawings and specifications. •This position requires the ability to work at an elevation of 10,000 feet; ability to thrive in a culturally diverse team environment; willingness to actively participate in team safety meetings and adhere to (and advocate for) safety procedures and protocols; and sensitivity to and respect of cultural and environmental issues. Desired skills: •Extensive experience with Rockwell Automation ControlLogix® is highly desired. •Experience in control system integration, commissioning and startup (including PAC, HMI, instrumentation, networking, communication, power distribution); detailed understanding of interface protocols to connected systems such as EtherNet/IP and BACnet. •Hands-on experience in a trade or as a technician is highly desirable. AURA is an affirmative action & equal opportunity employer. AURA actively supports efforts to broaden participation in all Observatory activities. Women and candidates from under-represented minorities are particularly encouraged to apply. On-line Job Posting and Application

I am not an expert nor do I play one on TV. I don't think what you propose is acceptable for Category 3. The enable input is a solid state device which is not safety-rated. I believe drforsythe has the correct implementation. That is redundant contactors on the output of the drive. I believe I found the document he was thinking of. In any case it shows Category 3 implementation of both controlled and uncontrolled stops.

I'm not sure that wireshark is really the best way. As there is a lot of traffic through a router but little traffic to a router. A quick look at my network with wireshark and my best bet is looking at IGMP protocol messages that are "Membership query," the source address is the address of my router. If that isn't it, the next thing is just start trying to connect to every IP address you see with a browser. Until you hit the router. (Go to Statistics...IP Addresses, that will give you a nice list of addresses.)

Without knowing more about the system, I would suggest you look at POINT I/O, such as the 1734-IE8C. If you already have a compatible communication network you could put three of these modules out at the field and all you have to bring back is the communications wiring. If you turn out to need 25 instead of 24 it's easily expandable. Just an alternative to multiplexing, may not be what your interested in.

I've currently writing a best practices/guidelines for a system I'm working on. The system consists of eight Guardlogix processors connected over EtherNet/IP using Stratix 8300 switches. Several of the GuardLogix systems are embedded in other subcontractors' systems. I will be doing the rest; I'm also co-ordinating the project. So, I want to write a document that outlines how to program and configure the system so that it will be easy to integrate and will have consistency between systems when troubleshooting years down the road. The project is nearing the end of the conceptual design stage. Things I have on my list to include are IP address, subnet masks, VLANs. Naming convention for processors, I/O modules, controller-scoped tag names. I'm providing sample code for various functions, emergency stop, end-of-travel limits, etc. 1) What should I include in such a document? 2) What should I not include in such a document? If you've worked on such a project in the past what pitfalls were there. What did you do right; what did you do wrong?

Wow, then that's quite the instrument that can measure with a precision of 1 part in 26,000. Too bad the accuracy is off by a factor of around 3846. I've seen some out of whack spec sheets but that is crazy. Anyway I'm glad you got what you needed out of it and I hope you properly dispose of that speculation, I mean specification sheet.

But it still doesn't quite add up, if it really is .26 pulses per gallon. You sure the spec isn't .26 gallons per pulse?

Obviously you can't measure fractional pulses. But if you were measuring a very large flow rate and didn't need precision then 3.5 gals/pulse would make sense. Or if you wanted to know the approximate total but didn't care about fine resolution it would work. If you used a 32-bit counter you could totalize up to 150 million gallons. If you needed to use this device to measure a small volume, then the proportional output and a little calculus would work nicely. Volume=Rate/Time.

For what it is worth, while I can't say I like the 3 minute boot time, I don't really see it as a problem. I've been running our Stratix 8300's for nearly a year without once having it reboot because of flaky power. No UPS and only one power supply connected. It even ran through a bunch of brown outs that caused PCs around the building to reboot.

You will find that the power pins for each group are connected internally. You can easily check this with power turned off and an ohmmeter without risk.

Michael is right. Goto Alarms...Alarm Setup...Advanced tab and select the display you want to open in the Display...Current alarms box. You must also go to the Messages tab and check the Display box for alarm messages you want to open the above display.

It sounds to me that something in those two pop-ups are trying to either open more pop-ups or change each others displays. You run out of memory because it may be trying to open to many displays simultaneously. A flickering display sounds like one pop-up is doing the something and the other is un-doing it. I would double even-triple check what those pop-ups are doing. I would delete like half the things on the panel and give it a try. Then restore, delete the other half, and see if the problem goes away. I really don't know what is going on but it sounds like you have to resort to the basic shotgun troubleshooting approach.