Wiring Connections For Properly Grounded System; Encoder Wiring - O. Thompson Microflite Ultra 2000 Installation & Adjustment Manual

on concrete beam pockets, and the earth connection is inadequate.
2. A sprinkler system water pipe is not adequate because the sprinkler system is, in
most cases, isolated from a free flowing earth water source.
If either of the two methods above are chosen for ground, and a true electrical ground is later
introduced to the system, a difference in potential can occur between the assumed ground and
the actual earth ground. This may lead to unstable operating conditions, and the possibility of
electrical shock to passengers or personnel.
3. A water pipe is an adequate ground only if the water in the pipe is connected to a
continuous city water source.
Wiring Connections for Properly Grounded Systems
4.1.12
1. An uninterrupted ground wire of at least #8 AWG wire should be run from each car
controller cabinet chassis or backplate to earth ground. The connection at the car controller
must be scraped free of paint so the ground connection can be made to the bare metal of
the enclosure. The car controller should read less than 1 ohms to ground with the power
off.
2. Ground straps, or short loops of ground wire should be run from the controller ground
connection to the primary duct connections.
3. An uninterrupted #8 AWG ground wire should be run from the hoist motor frame to the
controller ground. Wherever the ground connection is made on the hoist motor should be
free of paint.
A continuous looped ground wire should be run from each hall lantern and position fixture
4.
box to controller ground. The ground connection at each fixture should make an electrical
connection to the bare metal of the fixture box and its cover. This connection should be
free of paint.
An uninterrupted ground wire of a minimum of #14 AWG should be run from a termination
5.
point on the cab to the controller ground.
An uninterrupted ground wire should be run from the cab enclosure to the ground terminal
6.
on the cab to protect passengers and personnel from electrical shock.
An uninterrupted ground wire should be run from each car operating panel to the ground
7.
terminal on the cab to protect passengers and personnel from electrical shock.
An uninterrupted ground wire should be run from the dispatch cabinet chassis or backplate
8.
to earth ground. The connection at the dispatch cabinet must be scraped free of paint so
the ground connection can be made to the bare metal of the enclosure.
9. A continuous looped ground wire should be run from each hall push button station to the
dispatch or controller ground.
4.2 Encoder Wiring (Magnetek DSD 412 & HPV 900 only)
The encoder used on the Magnetek DSD 412 and HPV 900 drives is a quadrature encoder. The
signals from the encoder are:
Revision: AA 2.2
Microflite Ultra 2000
Printed 03 - 15 - 03 4 - 5