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4. A front panel mounted red alarm indicator LED and chassis mounted alarm relay with form "C", 2 amp 0 110 VAC contacts shall be provided for each process variable channel. 5. The unit shall utilize a microprocessor controlled stepper motor for positioning each recorder pen proportional to the corresponding input channel 1-5 VDC process variable signal. A clutch shall be part of the pen positioning mechanism to prevent damage to pens or motor and eliminate the need to recalibrate the unit if the pens are accidentally moved. A pen control lever shall be provided for raising and moving pens away from the paper to facilitate the chart replacement. 6. The servo chart drive module shall have all internal components enclosed within a completely sealed metal housing. Motor position feedback shall be provided which provides infinite resolution. Wire wound slide wire potentiometers are not acceptable as feedback elements. No brushes or gears are to be used in the motor assembly. 7. The electronics shall have a sheet metal housing designed for RFI protection. All circuit boards shall be coated for protection from hostile atmospheres. 8. Voltage or current isolators shall be provided on each process variable input when necessary for signal compatibility with the external sourcing circuits and nonisolated common connections. 9. The instrument case shall be of reinforced high strength construction complete with a fully Basketed door, lockable latch, and acrylic window. The case and door color shall be gray. The construction shall provide environmental protection of NEMA type 3. The instrument shall be designed for flush mounting. All connections shall be easily accessible in the bottom of the case. 10. The chart recorder shall be suitable for operation in an ambient temperature range from 32 to 122 OF. The electronics shall be powered from 120 VAC. The electronics shall operate satisfactorily with AC line power fluctuations of +10% and -15% and frequency between 57 and 63 Hz. 11. The instrument shall have, at a minimum, an accuracy of +/- 0.25% of span, a repeatability of 0.25% of span, a hysteresis of 0.30% of span, and a deadband of 0.1% of span. The speed of response shall be less than 6 seconds for a 90% step change in the input. 12. Disposable fibertip pen cartridges shall be used for chart inking. ELECTRICAL 16000 - 29