Description
PFEA111/112 For timing tests, the signal generator must be capable of triggering into step-wise
changing of frequency or ramping down to a pre-selected frequency in only a few
milliseconds.
Connect the Signal Source and PFEA111/112 Timer Start triggers as shown in
FIGURE 7–12: Frequency element testing on page 7–44.
Set the voltage to rated VT secondary value, the current to rated CT
secondary, and the pre-trigger frequency to the nominal frequency (60
or 50 Hz).
If current sensing is not enabled, it is not necessary to connect the
current signal.
Set the post-trigger to 0.5 Hz PFEA111/112 below the setting for underfrequency 1.
Reset all targets and relays, if necessary.
Reset the timer.
Initiate the frequency step and timer start.
The Interval Timer will record the operating time of element. Compare
this time to the S4 ELEMENTS FREQUENCY UNDERFREQUENCY 1
UNDERFREQUENCY 1 DELAY setpoint value:
Provided that the operate times are not scattered over a wide range, it may be desirable to
repeat this test several times and average the results. If there is a wide scatter, verify the
test setup and ensure the signal source behaves in a consistent manner.
PFEA111/112 Current input function (voltage input disabled):
If the frequency elements are using the winding 1 phase A current signal
as a source, verify the operation of the element using the instructions
below.
Using the variable-frequency current source connected to terminals H1
and G1 with no voltage connections, set the frequency to 60.00 Hz (or
50.00 Hz) and the amplitude to the rated CT secondary current.
Monitor the appropriate trip and auxiliary relays.
Reset all alarms and indications.
The display should remain unchanged with no trip indications.
Slowly decrease the frequency until the output relay(s) operate.
Check that the frequency at which operation took place is the selected
frequency setting.
Slowly reduce the current.
Note the current at which the output relay(s) reset.
Check that this dropout current is the minimum operating current
selected in the settings.
Note
If current sensing is not enabled, then the element will continue working all the way
down to a current level of 0.02 × CT A.
Increase the current back to nominal. PFEA111/112 Verify that the relay(s) operate.
Check that the Trip and Pickup LEDs are on and one of the following
trip messages is displayed:
LATCHED: Underfrequency 1 or OPERATED: Underfrequency 1
Slowly increase the frequency until the Pickup LED and output relays
reset.
Note the dropout level, which should be the pickup plus 0.03 Hz.
Check that the Trip LED is still on.
The trip message remains on if the UNDERFREQUENCY 1 TARGET
setting is Latched; if set to “Self-Resetting”, the message resets when
frequency is above the setpoint.
For timing tests, the signal generator must be capable of triggering into step-wise
changing of frequency or ramping down to a pre-selected frequency in only a few
milliseconds.
Connect the signal source and timer start triggers as shown in FIGURE
7–12: Frequency element testing on page 7–44.
Set the current to rated CT secondary value, no voltage connection, and
the pre-trigger frequency to the nominal frequency (60 or 50 Hz).
Set the post-trigger to 0.5 Hz below the underfrequency 1 setting.
If necessary, reset all targets and relays.
Reset the timer.
Initiate the frequency step and timer start.
The Interval Timer will record the operating time of element.
Compare this time to the S4 ELEMENTS FREQUENCY
UNDERFREQUENCY 1 UNDERFREQUENCY 1 DELAY setting
Why are the prices of many products of our company more competitive?
(1) Source purchase to reduce the price difference in the intermediate phase
(2) Stable channel and more guaranteed supply
Lead time problem
(1) For the spot products in stock, the delivery can be arranged on the same day after the contract payment is signed
(2) Order products and deliver according to the quoted delivery date
Xiamen Xiongba adheres to the enterprise philosophy of “improving the value of spare parts supply chain”,
For the simple purchase procedure of spare parts, ensure that they are delivered to the site in a timely manner, and help users reduce the risk of downtime caused by the shortage of spare parts
The emergency spare parts support service is complete, and the user can customize the spare parts. The quality of the spare parts is reliable. All the spare parts provided enjoy a one-year super long warranty
Spot stock, fast response, reduce user capital investment, improve spare parts utilization, spare parts replacement!
Details: If you need urgent delivery orders, please feel free to contact us, and we will try our best to meet your needs.
Price problem: If you find that other suppliers offer cheaper prices for the same product, we are also willing to provide you with reference prices and give you further discounts.
Contact us:+86 180 6092 3929
Mail: 2235954483@qq.com
Contact: Chen