We've discussed before how difficult vendors make your lives when they discontinue product lines well before we think they should (see When PLCs are Discontinued).  Suddenly you are faced with a decision of taking out the discontinued product and replacing it with your vendor's recommended solution (or finally letting the competitor's salesman in for a visit) or trying to get by repairing the parts that may fail or buying remanufactured products until your budget allows for a conversion.

If you find yourself needing to convert, your vendor doesn't always have a plan in place to give you some of your initial investment back.  Meaning, they may give a small discount off your new hardware, but they're likely not to give you much, if any, of a credit in trade towards the hardware you are taking out.  Why do they want to take it back anyway? And any credit doesn't offset the costs of re-wiring and re-programming the system.

So we have created our own PLC Trade In Program - simply send us a list of the PLC parts you are taking out of your current system and would like to trade in, and we will send you an offer for the parts.  In the vast majority of cases, we will offer you more for your parts than the manufacturer will.  GE, Allen-Bradley, Siemens, whatever you don't have need of.

As well, you will probably be left over with some spares for this older system.  List those parts too - we'll give you an offer on all of it.

This is a great way to offset the investment in the new technology and helps to ease the price of obsolescence.

Fill out our Trade In form for a quick quote on your unwanted PLC parts.

Recently, we had a customer who wanted to upgrade from a GE IC693CPU364 to a GE IC693CPU374 because they believed the CPU374 had more password characters.  Here is our Senior PLC Engineer's answer:

No, it is not true. The maximum length of the password is 6 ASCII characters whether it is an IC693CPU364 or an IC693CPU374. The only length restrictions that I have found is if the user is using Logicmaster 90 or a Hand Held Programmer, both of which limits the length to 4 ASCII characters. I have done some testing and I have found that the password can contain any ASCII character except a space and a tab and it is case sensitive. I believe this will fulfill the complexity requirement for your applications.

As far as the CPU364 is concerned, it would be better if they were replaced by CPU374s because the CPU364 has been discontinued for a few years. The programs in the CPU364 are directly transportable to a CPU374. All that would be needed would be a configuration change in the folder. The primary ‘gotcha’ in converting to CPU374s is that the CPU374 will use up the standard battery after 5-6 weeks of power-down time (versus 6 months for the CPU364). I would recommend that if CPU374s are installed, an auxiliary battery (IC693ACC302) should be installed with each one. This will provide 15 months max. power-down backup capability. An alternative to the CPU374 would be to use the CPU372, which has half the memory capacity at a lower price. However, this would require converting their programming s/w from VersaPro to Proficy Machine Edition (VersaPro does not support the CPU372) and making sure that a high capacity power supply is used with the CPU (Proficy requires that a high-capacity p/s be used with the CPU372 and CPU374).  (To learn how to install an IC693ACC302 for use with an IC693CPU374, go to our video library).

In addition, Qualitrol International will buy any used IC693CPU364 modules that you take out of a system.  Simply call us at 1-800-784-9385 and we will give you all of the details.