natus 60/65, Instruction Manual

Page: 36 / 96

OLYMPIC SMART SCALE
® Model 60/65
Page 3-17
Section 3: Service
Adjusting the Zero Offset
To adjust the zero offset:
1. Place the scale on blocks high enough to allow access to
potentiometer ports on underside of the scale. Ensure that the
tray is in place.
2. Access counts mode by pressing Reweigh while turning on the
scale ( On/Off ). Raw AD counts are shown.
3. Ensure that the tray is on the scale, then place a 7500-gram
weight on the tray. (The weight is available from Natus Medical,
catalog no. 56315).
4. Locate the potentiometer port for VR4 (see label on underside
of scale).
NOTE: For some cart-mounted scales the VR4 is
accessible via the cart. On these scales, the labeled VR4
port is located under the top shelf, to the right. Earlier scales
require removal from the cart to access the VR4.
NOTE: The scale enclosure need not be removed for VR4
adjustment, tray replacement, or calibration adjustment.
5. Adjust VR4 until the counts are 32768 ±10.
6. Recalibrate the scale (see
Calibration Procedure
on page 3-2),
and test the accuracy with two known weights other than 7.5 kg
(preferably one weight greater than 7.5 kg and the other less
than 7.5 kg).
NOTE: If displayed counts cannot be brought into range
by adjusting the VR4, return the scale to Natus Medical
for service.
NOTE: Recalibrate the scale before use.
Fig. 3P
On some models, access to the
VR4 adjustment is via the cart
VR4
Underside of scale, VR4 location
Cart, VR4 location
VR4
front
back