Dummy Loads

Dummy loads permit testing of pulsed power systems under known load conditions. These devices are coaxial-cable fed and represent a nominal impedance of 50 Ohms to the pulse source. This load impedance is predominantly resistive with a minimum reactive component. The internal construction consists of a stack of ceramic toroidal resistors and hv terminal housed in a polycarbonate tube. This assembly is grounded to the cover using continuous pressure from a spiral-wave spring at the base. To increase the operating voltage, the surrounding void as well as the resistor stack can be filled with a dielectric medium. A quick-disconnect fitting and purge valve allow filling with the recommended internal dielectric medium (not supplied). A 2-m (6') length of cable is provided with each load; the load end is fitted with our reentrant connector while the other end is unprepared for interface to the user's pulser. Note that these loads are for single pulse applications only and are not intended for repetitively pulsed usage. The DL-102 load is typically used with our smaller mini-Marx generators.

Standard Dummy Loads
Model Maximum
Voltage, kV
Resistance,
Ohms
Maximum Pulse
Energy, J
Internal Dielectric
Medium
Cable
Type
DL-101 40
120
50 1200 Air
SF6
RG-218/U
DL-102 400 50 6000 Oil RG-218/U
DL-102C 500 70 8400 Oil DS-2134


Model DL-101
(7.2 cm diameter x 25 cm height)

Model DL-102C
(8.9 cm diameter x 30 cm height)

Custom Dummy Loads

Much larger dummy loads utilize our aqueous-electrolyte resistor technology, e.g., the DL-104 system employed with our MV-1 Marx generator. Liquid resistors afford the ability to quickly change resistance by remixing the solution with a different electrolyte concentration. For other applications, custom ceramic resistors may be a better choice, as exemplified by the DL-107 system which utilizes large disk resistors configured as 10 trays with 3 resistors per tray. Trays act as heat sinks and the resistor is cooled by natural air convection. Six control rods, inserted from the bottom of the device, progressively short each section allowing adjustment of resistance.

DL-104 aqueous-electrolyte dummy load:
44-cm pulse line, 17-Ohm line impedance, 6.5-liter
volume, 3-120 Ohm adjustable load resistance
(Na2CO3 solution)
DL-107 adjustable ceramic resistor:
DS-2248 coaxial cable fed, 0.05-0.50 Ohms,
>50 kJ per pulse (shown with cover removed)

Pricing for standard dummy loads may be obtained from the links given on our Sales page. Specifications are subject to change without notice. Inquiries for additional product information are welcome!

Last revision: 12 January 2009

©Copyright 2001-2010 R. E. Beverly III and Associates