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2-12

MST-MHT SERIES 071320

2.9.1

LOAD CONNECTION WITH LOCAL ERROR SENSING

The most basic power supply/load interface is a 2-wire connection between the power supply
output terminals and the load. This connection method employs local error sensing which con-
sists of connecting the error sense leads (terminals S1+ and S2–) directly to the power supply
output (terminals O1+ and O2–). Its main virtue is simplicity: since voltage regulation is main-
tained at the power supply output, the regulation loop is essentially unaffected by the imped-
ances presented by the load interconnection scheme. The main disadvantage is that it cannot
compensate for losses introduced by the interconnection scheme and, therefore, regulation
degrades directly as a function of distance and load current. The main applications for this
method are for powering primarily resistive and relatively constant loads located close to the
power supply, or for loads requiring stabilized current exclusively. The load leads should be
tightly twisted to reduce pick-up.

2.9.2

LOAD CONNECTION WITH REMOTE ERROR SENSING

If the load is located at a distance from the power supply terminals, or if reactive and/or modu-
lated loads are present, remote error sensing should be used to minimize their effect on the volt-
age stabilization. A twisted shielded pair of wires from the sensing terminals directly to the load
will compensate for voltage drops in the load interconnection scheme (up to 0.5V maximum per
wire); the termination point of the error sensing leads should be at or as close as practical to the
load. Adapter Kit 219-0618 includes capacitive filtering, eliminating the typical requirement for
additional filtering capacitors. If adapter Kit 219-0618 is not used, it is recommended that some
amount of local decoupling capacitance be placed at the error sense termination point to mini-
mize the risk of unwanted pick-up affecting the remote error sense function. For very long power
module/load interconnecting cables and/or reactive loads, it may be necessary to add decou-
pling capacitors between the power and sense terminals at the power module side of the cable
to suppress oscillation due to cable inductance. A general recommendation is to install a net-
work of one (1) 10µF, 6.3V capacitor paralleled by one (1) 0.1µF ceramic capacitor across each
output sense pair (pins 6 to 5 and 3 to 2, respectively).

NOTE: As electrolytic capacitors are normally polarized make sure that the positive (+) terminal

of each one are respectively connected to the +V (pin 6) and -S (pin 2) pins.

TABLE 2-5.  DC OUTPUT CONNECTOR/ADAPTER KIT TERMINAL DESIGNATIONS

MST-MHT SIGNAL

CONNECTOR TERMINAL

(See Figure 2-6)

Output Terminal 1 (+)

O1+

Output Terminal 2 (–)

O2-

Sense Terminal 1 (+)

S1+

Sense Terminal 2 (–)

S2-

Current Share Bus

CS

Module Chassis

GND

NOTE: The polarity for the terminals indicated above are for output enabled and polarity

not reversed (normal).

Содержание MST 100-2MHT

Страница 1: ...revision for your par ticular model and serial number 3 The contents of this manual are protected by copyright Reproduction of any part can be made only with the specific written permission of Kepco I...

Страница 2: ......

Страница 3: ...ired equipment rack utilizing a three wire grounded mains connection See wiring section of this manual for complete electrical wiring instructions EN61010 1 2001 Cl 6 10 1 4 This power supply has seco...

Страница 4: ...performing any servicing This product is designed for use with nominal a c mains voltages indicated on the rating nameplate The PROTECTIVE EARTHING CONDUCTOR TERMINAL must be properly con nected prio...

Страница 5: ...ounding 2 6 2 6 2 D C Output Grounding 2 6 2 7 Preliminary Check out 2 7 2 7 1 Required Equipment 2 7 2 7 2 Initial Setup 2 7 2 7 3 Checkout Procedure 2 9 2 8 Power Module to Load Interface 2 10 2 9 C...

Страница 6: ...ode Protection 3 7 3 9 Calibration 3 8 3 9 1 Equipment Required 3 8 3 9 2 5 Volts Reference Adjust R49 3 10 3 9 3 Output Voltage EO Zero Adjust R11 3 10 3 9 4 Current Sense Zero Adjust R50 3 10 3 9 5...

Страница 7: ...iguration for Preliminary Checkout 2 9 2 5 Output Impedance vs Frequency 2 11 2 6 Connector Locations and Pin Assignments 2 13 3 1 Calibration Test Set up 3 10 1 1 MST MHT Model Parameters 1 2 1 2 MST...

Страница 8: ...iv MST SERIES 071320 FIGURE 1 1 MST POWER SUPPLY...

Страница 9: ...nts current share hot swap built in polarity reversal constant current mode and greater power 180W to 200W MST MHT power modules employ a switch mode preregulator for high efficiency and power density...

Страница 10: ...x TABLE 1 2 MST MHT GENERAL SPECIFICATIONS SPECIFICATIONS RATING DESCRIPTION CONDITION INPUT A C Voltage nominal 100 250V a c Single phase range 90 264 Va c Brownout Voltage 85Vrms Frequency nominal 5...

Страница 11: ...condition Isolation Output Case 500 V d c Display Voltage 3 5 Digit LED red Front panel For reference only Current 3 5 Digit LED red Status Indicators Voltage Mode Green LED Current Mode Amber LED Cur...

Страница 12: ...ilent HP 66000 Series PHYSICAL Type of Construction Enclosed plug in style includes status LEDs two digital meters handle and ON OFF switch Cooling Internal D C Cooling Fans Exhaust to rear Module Dim...

Страница 13: ...MST MHT SERIES 071320 1 5 FIGURE 1 1 MST MHT POWER SUPPLY MECHANICAL OUTLINE DRAWING...

Страница 14: ...isabling the MST MHT as a current source means shorting the power supply s output terminals Polarity reversal relays are installed but not supported at this time If polarity reversal is needed refer t...

Страница 15: ...Adapter Additional accessories are listed in Table 1 3 TABLE 1 3 ACCESSORIES ACCESSORY PART NUMBER USE OUTPUT LOAD CONNECTOR ADAPTER supplied with RA 55H Rack Adapter KIT 219 0618 Allows output load c...

Страница 16: ......

Страница 17: ...lt age and frequency ranges without adjustment or modification 2 4 COOLING The power transistors and rectifiers in the MST MHT Power Module are maintained within their operating temperature range by m...

Страница 18: ...rce see PAR 3 2 1 CURRENT MODE indicator amber LED Goes on to indicate MST MHT is operating as a current source see PAR 3 2 2 POLARITY REVERSED indicator green LED Goes on when negative output program...

Страница 19: ...h the top of the unit see Figure 2 2 and can be changed in accordance with Table 2 4 This address is set at Kepco to 1 NOTES 1 Although 31 unique addresses are provided the maximum number of instrumen...

Страница 20: ...1 0 0 13 0 1 1 0 1 14 0 1 1 1 0 15 0 1 1 1 1 16 1 0 0 0 0 17 1 0 0 0 1 18 1 0 0 1 0 19 1 0 0 1 1 20 1 0 1 0 0 21 1 0 1 0 1 22 1 0 1 1 0 23 1 0 1 1 1 24 1 1 0 0 0 25 1 1 0 0 1 26 1 1 0 1 0 27 1 1 0 1...

Страница 21: ...in use refer to PAR 2 5 1 to change the address setting NOTE If the Power Module is already installed in a Rack Adapter and it is necessary to change the control bus address the Power Module must firs...

Страница 22: ...formance considerations and safety requirements For optimum performance certain rules must be observed These rules are described in detail in the following paragraphs 2 6 1 SAFETY GROUNDING National a...

Страница 23: ...circuit and returned to ground with a single wire This method is dependent on the specific application 2 7 PRELIMINARY CHECK OUT 2 7 1 REQUIRED EQUIPMENT Host computer w communication cable for select...

Страница 24: ...d i e a c power applied to the Controller first and MST MHT power modules last the operator must send an IEEE 488 Device Clear command via the Host Computer prior to issuing other commands For proper...

Страница 25: ...mands from the host computer to set the MST MHT Power Module to Voltage Mode program output voltage to EMAX current limit to IMAX and enable the output e g for MST 36 5MHT issue the following commands...

Страница 26: ...current MEAS CURR Verify that read back current is IMAX e g 5A for MST 36 5MHT 2 8 POWER MODULE TO LOAD INTERFACE The general function of a voltage or current stabilized Power Module is to deliver rat...

Страница 27: ...put of the Power Module is step programmed The load is reactive Dynamic output response of the Power Module is of concern 2 9 CONNECTION GENERAL All input and output connections between the Power Modu...

Страница 28: ...terminals directly to the load will compensate for voltage drops in the load interconnection scheme up to 0 5V maximum per wire the termination point of the error sensing leads should be at or as clo...

Страница 29: ...071320 2 13 2 14 Blank FIGURE 2 6 CONNECTOR LOCATIONS AND PIN ASSIGNMENTS NOTE To remove Adapter Kit 219 0618 refer to Kit 219 0618 RA 55 Connector Adapter Kit Instruction Sheet see PAR 1 1 for downlo...

Страница 30: ......

Страница 31: ...ST 488 27HT Controller see PAR 1 1 Table 3 1 lists the catastrophic status messages along with the related MST MHT Power Module condi tion 3 1 2 TIMING REQUIREMENTS FOR A VALID STATUS After sending a...

Страница 32: ...n or equal to the critical value indicated above will result in automatic return to normal operation 3 2 2 CURRENT MODE In this mode the Power Module is programmed to behave as a current source The us...

Страница 33: ...Power Modules is limited to a maximum value which may in some cases be inadequate to fully discharge all external load capacitance To ensure dry relay switching for all output conditions the user mus...

Страница 34: ...tage range GL Io VMAX For an ideal current source a no load condition is then defined as infinite conductance zero impedance since this is the only load condition at which the delivered power is zero...

Страница 35: ...true if modules are disabled sequentially 3 6 SERIES OPERATION MST MHT Power Modules are designed to allow series operation to achieve higher output volt age if desired Series operation requires deta...

Страница 36: ...unt equal to 10 of the Power Module s rated voltage the circuit initiates a fault shutdown procedure as described in PAR 3 7a The tolerance of the fixed overvoltage hardware trigger is the minimum val...

Страница 37: ...OUTPUT FAULT indicator to determine recovery action If the indicator is on refer to PAR 3 7 1 for recovery If the indicator is off send RST to recover The open sense power wire protection circuitry ca...

Страница 38: ...d in Table 1 1 IMAX is the maxi mum output current of the unit as listed in Table 1 1 for 45 C 3 9 1 EQUIPMENT REQUIRED Calibration of MST MHT Series Power Modules requires the following equipment Hos...

Страница 39: ...MST MHT SERIES 071320 3 9 FIGURE 3 1 CALIBRATION TEST SET UP O2 S2 CS GND S1 O1...

Страница 40: ...arison amplifier to be zero for a pro grammed output voltage of zero 1 Configure DC OUTPUT connector as shown in Figure 3 1 and open S2 2 With the load disconnected issue commands from the host comput...

Страница 41: ...ge Mode program current limit to IMAX output voltage to EMAX and enable the output 2 Verify VOLTAGE MODE and OUTPUT ENABLED indicators are on 3 Connect the voltmeter to DC output connector see Figure...

Страница 42: ...Current Mode with output disabled to avoid drift due to temperature fluctuations 2 Enable the output and verify that CURRENT MODE and OUTPUT ENABLED indicators are on 3 Record the output current as m...

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