Thermowell; Instrument Drive (Id) - Honeywell RABO G65 Instruction Manual

®
ELSTER RABO Rotary Gas Meter

13. Thermowell

All RABO meters come equipped with two (2) ¼" NPT auxiliary
ports on the meter body [Figure 18], which can be used for
sensing pressure and temperature of the flowing gas. A
thermowell is required when using a temperature sensing
device. Thermowells are available as accessories to the
meter.
NPT AUXILIARY PORTS
Figure 18. Auxiliary ports
a) Installing a Thermowell
1. If meter is not installed in the gas piping, go to Step 5.
2. Slowly open bypass valve.
3. Slowly close the meter's outlet valve, then the inlet
valve.
4. Slowly, completely depressurize the meter piping.
5. Remove one of the plugs in the meter body by
using a ¼" hex key.
6. Apply Teflon tape or pipe dope to the male threads of
the thermowell. Wipe excess pipe dope off the
thermowell probe and leading threads to ensure no
pipe dope enters the metering chamber.
7. Screw the thermowell into the meter and tighten to
18 ft-lbs.
8. Re-pressurize the meter as instructed in Start-up/
Commissioning (see section 6).
15 Honeywell

14. Instrument Drive (ID)

All RABO meters can be retrofitted with an instrument drive,
or instrument adaptor plate. The ID provides a mounting
surface for instruments requiring mechanical rotational
input. The drive rate of the RABO ID is 10 cubic feet per 1
revolution in a clockwise direction. When
instrument, orient the instrument face to the FRONT edge of
the adaptor plate. The threads in the adaptor plate for
instrument mounting are 5/16" - 18.
Figure 19. RABO with Instrument Drive
a)
Retrofit a CTR (CTR = Uncorrected Mechanical Totalizer)
meter with an Instrument Drive (ID).
i) Remove index. See section 11. d) 1 to 11. d) 6
ii) Transfer the change gear from the CTR index to the ID
gearing and index assembly [Figure 14 and 20].
(1) Pry the change gear's locking collar off with a
knife blade or other similar object.
(2) Unscrew the change gear from the CTR index.
(3) Attach the change gear to the middle gear on the
back side of the ID gearing and index assembly.
(4) Reinstall locking collar to retain the change gear.
CHANGE
GEAR
LOCKING
COLLAR
Figure 20. Change gear installation on
ID gearing and index assembly
iii) Remove the magnet holder assembly from the meter
[Figure 21],
Magnet
holder
Figure 21. Magnet holder
installing an