Yokogawa RAMC - Manual (Page 67)

<8. SERVICE>
8-3
IM 01R01B02-00E-E 10th edition January 01, 2013 -00 All Rights Reserved. Copyright © 2003, Rota Yokogawa
8.1.4 Electronic transmitter
The electronic transmitter is maintenance-free. The electronic section is sealed and cannot be repaired. Since
the transmitter has been adjusted fully to the mechanical components at the factory, single components can
only be replaced with a reduction of the accuracy.
Solely the display and operation unit (LCD PCB) can be replaced. For this the unit has to be sent to service.
The current output can be adjusted by means of software. The current output test in chapter 6.2.11 determines
whether an adjustment is necessary. The adjustment is carried out according to chapter 6.2.6. The power
supply PCB of 4-wire units includes a fuse. For fuse replacement be sure to switch off the power supply. Only
use fuses with the capacity and characteristic as indicated in the specifications in section 9.5 or as imprinted on
the fuse holder.
8.1.5 Exchange of EEPROM and scale
Preparations:
· Check the commissioning-no., the key-code and the data of the new parts.
· Switch off power supply.
- For units with option /KF1 wait more than 2 minutes before opening the indicator.
- For RAMC with housing type 91 unlock the safety screw at the cover.
· Remove the cover of the indicator unit.
· Make sure that all accessible parts are not under voltage.
The pointer may not be twisted or bent on the axis!
Exchange of EEPROM:
The calibration-EEPROM can be damaged by electro-static discharge (ESD) . Therefore, only touch
insulated parts and never terminals.
The EEPROM is plugged in on the right side of the electrical angle transmitters and safeguarded with a latch
(s. fig 3-1 / 3-2).
· Unscrew the screw of the securing latch, but only a few turns!
· Turning the securing latch up, so that the EEPROM can be pulled out.
· Put in the new EEPROM (no wrong positioning possible).
· Turn the securing latch to below above the EEPROM and fix it with the screw.
Exchange of scale at units without limit switches:
· Unscrew the 2 screws of the scale.
· Pulling out the scale of the indicator unit to the left by raising the scale above the 4 corners for units with
housing 66. For units with electronic transmitter the scale must additional raised above the 2 buttons.
· Sliding the new scale from the left under the pointer correspondingly until the 4 corner holes click in the
footbridges for units with housing type 66 and the 2 buttons click in in the accompanying holes for unit with
electronic transmitter.
· Fasten the scale with the 2 screws.
Exchange scale at units with limit switches:
Please, consult to this the service department of ROTA YOKOGAWA.
Final jobs :
· Connect the cover of the indicator.
- For RAMC with housing type 91 lock the safety screw.
· Switch on power supply.
· Check function of the unit.
IMPORTANT
WARNING