4
The HALO I (models 8280/8281) has two pressure switches, one marked “ON/RESET” to switch
on the display and to reset the display after testing. The second switch marked “OFF” turns the
HALO off after use. The HALO II (models 9390/9391) has two pressure switches, one marked
“OFF/ON” to switch the display off and on. The second switch of the HALO II is marked
“TRACK/HOLD”. In the TRACK mode the readings will
follow the current and in the HOLD mode the reading
will display and hold the highest current. When
in TRACK mode, a sine wave appears in the lower
left corner of the display.
The HALO units have an automatic shut off feature
that will turn the unit off after approx. 10 minutes.
The HALO is powered by a replaceable, 9 volt lithium or alkaline battery. Under normal
conditions, a battery will provide approximately 50 hours of continuous use. A low battery
indicator is displayed on the left hand side of the display when the battery is low, as shown
in Figure 1. Incorrect readings may be displayed if the HALO is operating with a low battery.
USING THE EQUIPMENT
1. Inspect HALO and hotstick for any damage, cleanliness and proper working order. If
damage is suspected, remove from service and arrange for repair.
2. Attach the hotstick, which can be supplied by HDE as an accessory or by the user, to the
universal spline located at the base of HALO.
NOTE
- The load on the HALO should not exceed 22 lbs. (10kg) longitudinal or 11 lbs.
(5kg) in any other direction.
3. Turn the HALO on by pressing the “ON/RESET” switch (HALO I) or “ON/OFF” switch (HALO II)
for approximately 5 seconds. While the button is depressed a reading of 1888 will be dis-
played to indicate that all digits are functional. Note, the 1888 only appears momentarily
with the HALO II. The display will come ON and should display 0 to 2 on the HALO I and
00.0 to 00.6 on the HALO II.
NOTE
- It is very important that
the “ON” switch is held down for
the 5 seconds for the HALO I.
4. Place the HALO, using the
hotstick, over the conductor
to be monitored. Leave in
place for 5 to 10 seconds.
WARNING
- Do not bridge the
HALO from energized line to
ground or from line to line.
NOTE
- For best accuracy, the opening of the sensing coil (hook) of the HALO should face
away from any other energized conductors so as not to influence the reading. See Fig. 2.
NOTE
- When conductors are spaced closely, raise the HALO with the core parallel to the
conductors, then slip the coil over the desired conductor by rotating 90°. The sensing coil
of the HALO may pick up external signals from conductors if it passes within 12 inches
(0.3 meters) of a conductor while being lifted into position or lowered to the ground.
Care should be taken to minimize this situation by avoiding contact or close proximity
with conductors other than the conductor being tested.
Figure 1
Low battery indicator signal shown in
upper lefthand corner of display.
Figure 2
Current Carrying Conductors
Coil
Opening
Magnetic
Flux
Coil
Opening
Coil
Opening
