Lamp Monitor Unit - Number Of Current And Voltage Sensors - Siemens TC12 Installation, Commissioning And Maintenance Handbook

b) Using voltage sense transformers to produce a suitable logic signal direct from
the lamp drive voltage.
Note: If voltage sensors are used to monitor a dimmed 50-0-50 V RMS supply
(on the 50-0-50 V RMS side of the transformer), they will only work down
to the first dim voltage tapping (i.e. dimming to 66% of the nominal
undimmed voltage). The voltage sensors will not work with lower voltage
tappings.
If Voltage sense transformers (part number 667/1/22734/000) are used then these
connect to inputs as follows. There are four wires from the voltage sensors. Two
wires connect to the mains lamp drive voltage being monitored (Blue wire to
neutral, Brown wire to live). The white and black wires connect to the required
input on 40-way connector PL2. Connector PL2 has Input/Output cable
(667/1/22693/000) connected to PL2 (as described in section 3.2.5). Using a
suitable terminal block connect the white (ground) wire of the voltage sensor to the
white (ground) wire on the Input/Output cable and connect the yellow wire on the
voltage sensor to the appropriate coloured wire on the Input/Output cable
(corresponding to the required input number).
The voltage sensors should then be fastened (e.g. Tywrap) to a suitable point in
the cabinet, such as the cabinet cross-member or other free unobtrusive rail or
wire bundle.
A Ferrite clamp (part number 905/4/10616/000) is fitted over all wires from the 50
way connector, PL1, as close to PL1 as possible. The ferrite clamp should be
cable tied to a suitable point on the OTU mechanics to prevent it moving.

3.2.6 Lamp Monitor Unit - Number of Current and Voltage Sensors

LMU Configuration
Before the detailed configuration of an installation takes place, it is often
necessary to calculate the number of current and voltage sensors required. Tables
to assist with this are given on the next page. To use these, fill in the appropriate
information in the spaces provided and a final addition/subtraction of the values
will give the number of sensors required.
666/HE/43100/000
TC12 Installation, Commissioning & Maintenance Handbook
Leaving phase delays.
Use of phases that are not fixed in the stage.
Page 83
Ferrite Clamp
Issue 10