Often dabbling in the reselling and distribution business, Weschler Instruments offers many of the 5000 series analog meters originally manufactured by Hoyt Electrical Instruments. Once a staple across many industries, analogs like the 5000 series (including the 5015/5016, 5025/5026, and 5035/5036) have mainly been relegated to the I&C rooms of aging nuclear facilities, where NRC regulation and licensing mandates make it difficult to modernize.
Ranging in size from 1 ½ inches to 3 ½ inches, these small displays, commonly used on generators, operate primarily on DC moving coils and AC rectifiers. The traditional dust restraint and gasket sealing technique designed to allow for scale changes has long proved cumbersome and inefficient. Additionally, the troublesome needle of the analog era renders these units a paltry 2-3% accuracy range, with no background lighting to enhance the display from across a control room. Power requirements also check in with outdated specifications of 3–18VDC, 60mA max. It is clear that the 5000 series, along with its analog brethren, should have long been relegated to the nostalgic pages of instrumentation history. So why are they still on the market?
The answer is largely found in the difficulty and frustration common to finding suitable replacements for obsolete analog and even digital meters. This is doubly true of industries like the nuclear sector, where a spare unit must be on-site for every active instrument in the control room. If the inhibitive nature of finding replacements is why obsolete meters such as the Hoyt 5000 series are still used, then what can be done to facilitate modernization two decades into the twenty-first century?
Otek proposes a direct, efficient, and effective solution in its innovative Plug & Play (PNP) technology. From the 1 ½ inch size of the 5000 series to any size, shape, or function of any meter in an I&C room, Otek’s PNP series streamlines the replacement search with a single I/O module. This universal module, able to carry up to four signal conditioners at a time and covering over 50 input signals, fits into a compact Hub casing that plugs into the back of a PNP meter without any changing to the surrounding panel or wiring, and all without any soldering. The aforementioned scale changes of the 5000 series become infinitely more streamlined with the PNP’s unique “stick-on” scale plate design that uses One Size Fits All technology to apply directly to the front of the instrument, allowing for easy interchangeability of the scale plate without having to remove the instrument from surrounding panels.
Applicable to Mil-Spec and Class 1E standards, the PNP carries general specifications of ± 0.5% accuracy of the full scale ±1 LSD, temperature coefficient: ± 50 PPM/°C, an operating temp of -20 to +70°C, CMRR: >90dB@ 50-60Hz, humidity levels of 5-95% (non-condensing), front panel options for NEMA 3 or NEMA 4X, EMI/RFI Class1E adherence, power requirements for loop powered options at >10<100mW and external requirements at >50<200mW, and all with a 4½ digit display.
Whether you’re struggling to find a digital replacement that fits your wiring and panel requirements, or you’re simply looking to save money on your maintenance budget by reducing spare inventory, the PNP series can help revolutionize your application and overall efficiency.