RTT-1 Measures Relay Activation Times in msec
Test Power Utility Transfer Trip, Protective Relays, or any DC relay

  • Measures Relay Activation times in milliseconds with resolution to 25 microseconds
  • Reports Minimum, Maximum and Average Activation Time
  • Test Power Protection Relaying and Transfer Trip Operational Time
  • Use to Bench Test TDM versus Packet Network Performance
  • Powered by relay power supply, 12 to 60 VDC
  • Serial port for configuration and results
  • Indicators for Power and Relay Activation
  • Small, compact enclosure
  • Low Price - $250


The Relay Operation Time Tester (RTT-1) is a small, compact device that will activate DC relays and measure the relay activation time. When testing, the Output from the tester turns on the relay under test by sending a pulse. The Input connection measures the time between the tester output turning on and the relay response input turning on. Time is in milliseconds with the internal time resolution being 25 microseconds. The minimum, average, and maximum times are reported when running continuous tests. The typical application of the RTT is to measure the time it takes to propagate a Relay On event at one end of a communications link to the corresponding Relay On event at the other end of the communications link. These are typically bench tests where the near end relays and the far end relays are on the same test bench. This testing is often performed prior to deploying packet switched networks to replace TDM communications paths. It's necessary to characterize the relays being used before measuring the communications path time delays.

Tests Performed

The RTT-1 has the following test options:
  • g - go once (a one shot relay event)
  • r - run continuous
  • s - stop run
  • c - clear stats
  • w - save config (write to memory)
  • h - help (displays the help screen)
  • -+ adjust pulse width (1 to 1000 ms)
  • < > adjust delay (10 to 1000 ms)
timing diagram

How It's Used

The RTT-1 is typically connected to a 48v relay. It is controlled from a RS-232 terminal or PC running terminal emulation software. As the the Output Pulse Width is increased, the Input pulse time value increases. If the relay resonse is too slow (or the pulse width is set too small), the displayed result is an error.

When running continuous tests, the stats will only be displayed if the Delay Time is 500ms or more. If the Delay Time is set for less than 500 ms, the stats will be displayed only in summary and only after the Stop Run command is entered.

Sample Results:

test: 1, fail: 0
trip: 4ms, min: 4ms, max: 4ms, avg: 4ms
pulse: 9ms, min: 9ms, max: 9ms, avg: 9ms

Continuous with Delay Time < 500 ms
test: 53, fail: 0
trip: 4ms, min: 4ms, max: 4ms, avg: 4ms
pulse: 19ms, min: 19ms, max: 19ms, avg: 19ms

Continuous with Delay Time > or = 500 ms
test: 57, fail: 0
trip: 4ms, min: 4ms, max: 4ms, avg: 4ms
pulse: 19ms, min: 19ms, max: 19ms, avg: 19ms
test: 58, fail: 0
trip: 4ms, min: 4ms, max: 4ms, avg: 4ms
pulse: 19ms, min: 19ms, max: 19ms, avg: 19ms
etc. until a Stop Run command is received






Relay Port
Relay Control I/O
Control Port
Power and serial Ports

Questions? Phone us toll free at 800-432-2638

Item Number Description Price Buy Now!
RTT-1Relay Trip Time Tester $ 250 Qty:
9001158Optional 2 Amp 48 VDC power supply, 120-240 VAC input
Note: Most customers already have a 48 VDC power source.
$ 125 Qty:

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