參數(shù)資料
型號: 9325-8402
元件分類: 功率/信號繼電器
英文描述: POWER/SIGNAL RELAY, 3PST, MOMENTARY, 0.175A (COIL), 28VDC (COIL), 4900mW (COIL), 25A (CONTACT), 28VDC (CONTACT), PANEL MOUNT
文件頁數(shù): 10/13頁
文件大小: 757K
代理商: 9325-8402
Application notes
N°101
DERATING OF CONTACTS FOR DC VOLTAGES
ABOVE NOMINAL RATING
To establish a standard for the derating of relay contacts is, at best, a subjective practice. Limitations are governed by the type
of relay, contact gap, maximum voltage capabilities of the relay contact system, and the contact material.
The most common method is to derate the contacts by use of the Power Formula, using the known current and voltage.
This method is valid only for
Resistive Loads, and is an approximation only; keeping in mind the limitations mentioned above.
Power = IE (Current x Voltage)
I2 E2 = 2/3 I1E1
Example:
A designer is working with a 55 volt DC system and has a relay rated at 10 amps resistive at 28 volts DC.
What is the maximum current that can be switched at 55 Vdc.
I1 = 10 Amperes
E1 = 28 VDC
E2 = 55 VDC
I2 = ? (Current ratings at 55 VDC Resistive)
I2 E2 = 2 I1 E1/3
I2 = 2 I1 E1/E23
= 2 (10 x 28)/55 x 3
= 560/165
I2 = 3.4 Amperes at 55VDC
In addition, the user should always be concerned about the following:
1. Derating contacts that are rated for less than 10 Amperes at nominal voltage.
2. Derating contacts for use in system voltages above 130 Volts DC
Date of issue: 6/00
- 14 -
Page 1 of 1
相關(guān)PDF資料
PDF描述
9325-8523 POWER/SIGNAL RELAY, 3PST, MOMENTARY, 6325mW (COIL), 25A (CONTACT), 28VDC (CONTACT), PANEL MOUNT
9325-8788 POWER/SIGNAL RELAY, 3PST, MOMENTARY, 6900mW (COIL), 25A (CONTACT), 28VDC (CONTACT), PANEL MOUNT
055-939-9029ARD CRIMPHUELSE KOAX 1PIN Inhalt pro Packung: 10 Stk.
055-939-9049ARD CRIMPHUELSE KOAX 2PIN LIEGEND Inhalt pro Packung: 10 Stk.
9328DC 9328 SERIES, 8-BIT RIGHT SERIAL IN SERIAL OUT SHIFT REGISTER, TRUE OUTPUT, PDIP16
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
9325-8723 制造商:Leach International Corporation 功能描述:747-200 AIR LINE - Bulk
9325-8734 制造商:Leach International Corporation 功能描述:EM RLY 3PST-NO 25A 28VDC 160OHM BRKT - Bulk
9325-8994 制造商:Leach International Corporation 功能描述:CONTENT MANAGER - Bulk
932597100 制造商:Lumberg Automation 功能描述:CONNECTOR, GSA 3000 BLACK, VALVE, 3C + GROUND, SOLDER TERM, SCREW MOUNTING (UL)
932597-100 制造商:Hirschmann Electronics GmbH & Co Kg 功能描述:GSA 3P+E black appliance connector