AMS is happy to announce the introduction of the 5840 valve booster, also known as a Slammer. The DIN rail-mounted 5840 replaces the model 3840 Slammer board, which has been used with great success for more than 20 years.
The 5840 is used to improve the performance of hydraulic and air valves used in open loop flying press control. It makes a valve respond more quickly and consistently by applying a high voltage pulse of energy to the valve before dropping down to the normal 24VDC. The 5840 can be configured to produce 45, 60, 75 or 90VDC pulses.
Open loop flying press operations have two unique requirements: the reaction time of the press must be as short as possible and the reaction time must be very consistent. The following example shows how even a small variation in press reaction time can lead to a significant part length error:
Machine speed: 300 fpm (91 m/m) = 60 inches/second (1.5 m/sec)
Reaction time variation: 5.0 milliseconds
Resulting length control error = speed * reaction variance
= 60 inches/sec * 0.005 sec = 0.3 inches
(1.5 m/sec *0.005 sec = 7.5 mm)
The 5840 improves the response and consistency of the valve by maximizing the transfer of energy to the valve coil. Since the valves coils are rated at 24VDC, it is important to only apply the high voltage for a brief time to avoid damage to the valve. This concept has been tested in a lab as well as two decades of proven field experience. The following graph shows an example of the improvement seen with higher voltages. To measure the valve reaction time, we attached a LVDT to measure spool position when various voltages were applied to the coil. Testing was performed on a wide range of pneumatic and hydraulic valves commonly seen on press and boost systems.
One item to note is that it is important to not hit lower mass valve spools with too high of a voltage or they may bounce. If the valve bounces, it will actually cause the reaction time of the valve to get worse than it would have with just 24 volts. For this reason, the 5840 can be set to one of four voltages. The previous model, the 3840, worked well at 60V, but we found that the performance of some heavier valves could be improved with voltages up to 90V.
The 5840 was designed for high-performance applications. It is capable of switching 8 amps with a 90V pulse 4 times a second (cycle rate is higher with lower pulse voltages). This has been extensively tested at 65C (155F) ambient temperatures.
If you have any questions about how this product can improve the performance of your machine, please contact us.