Dover OPW 788 Series Quick Start Manual

790 Series Counterbalance
Equipment: Torsion Balance Type: 790A,B,C
Balance Unit for Balancing Loading Arms
Suitable for: Loading Arm Balancing
Easy, Precise Adjustment
Specifications
Type:
Right-Hand: 790A-0020 (White),
790B-0030 (Yellow), 790C-0050 (Red)
Left-Hand: 790ALH-0025 (Black),
790BLH-0035 (Gray), 790CLH-0045 (Orange)
Working Temperature Range:
-40°F to 176°F (-40°C to +80°C)
Installation
Spring Unit Assembly
1. Position balance unit on the bosses at back of swivel joint.
2. Fix balance unit with Bolts and Lock Washers.
3. Attach backside of Link Arm [17] to Spring Arm [15] with Pin
[16] and 2 Retaining Rings [14].
4. Remove the 4 Socket Head Screws [18] and take Snubber
Block [26] off.
5. Raise loading arm to highest position (as vertical as possible).
Adjustment
When to adjust torque
A. To raise loading arm higher or for more lifting action INCREASE torque.
B. To decrease loading arm vertical travel or to slow the rate at which the arm rises, DECREASE torque.
C. Note: Prior to any disassembly, Spring balance tension should be completely relieved to allow safe disassembly of level arm.
Torque
For more lifting action increase torque.
For less lifting action decrease torque.
Place ¾"socket wrench on worm gear hex drive.
To INCREASE torque rotate the worm gear hex drive
counterclockwise (to the left).
To DECREASE torque rotate the worm
gear hex drive clockwise (to the right).
NOTE: Prior to any loading arm disassembly, spring tension should be
completely relieved. Tip: To relieve tension, arm should be pushed up as
much as possible and supported while spring tension is relieved. Spring
coil will be loose in housing when completely relieved of tension.
No special tools required
6. Attach front side of Link Arm [17] to mounting ears on loading
arm with Pin [16] and 2 Retaining Rings [14].
7. Check balancing action by pulling down the arm. If adjustment is
necessary, follow adjustment instructions below.
8. Install lock-down unit 788-L, if used, by following 788-L
installation instructions.
9. Replace Cover [21] using alignment pins [1] and latches [22].
www.opw-es.com
PART #H30790PA
790-SERIES-IOM-EN-01/2021
Easy-To-Use
Spring Cover Latch
Worm Gear Hex Drive