Ametek Z-tron IV, Инструкция по установке и эксплуатации

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22
Z-tron IV
TM
Point Level Control
Section 5: Troubleshooting
5.1 Introduction
The Z-tron IV Level Control is a solid-state device with
no moving parts other than its relays, and requires no
maintenance or adjustments. The units are designed to give
years of unattended service.
A spare electronic chassis is recommended for every 10 units
so that, in case of a failed unit, a critical application will not
be delayed while the unit is returned to the factory for repair.
Use the following troubleshooting procedures to check out the
Z-tron IV Level Control. If attempts to locate the difficulty
fail, notify your local Drexelbrook representative, or call the
factory direct at +1 215-674-1234.
5.2 Testing Electronic Unit
It is recommended to begin with Electronic Unit:
1. Verify that green LED is illuminated and the proper
voltage is applied to the electronic unit.
2. Change fail-safe selector switch (Fig 3-1). If red LED
and relay do not change states, electronic unit has
failed.
3. On the back of the electronics unit (side opposite power
connections) remove the probe wires from under the
blue & red screws.
4. With the instrument in High Level Fail Safe turn the
setpoint adjustment counterclockwise (CCW) until the
red LED is on (red LED on indicates that the relay is
deenergized and the unit is in the alarm condition).
5. Turn setpoint adjustment slowly clockwise (CW) until
the relay just operates. (red LED off).
6. Rotate setpoint adjustment back and forth about this
point, observing travel of screwdriver between relay
pull-in and relay drop-out. If properly operating,
screwdriver should travel less than ¼ turn to operate
the relay. If not, electric unit has failed.
5.4 Testing Relay Circuits