How much power is required for mark-vie control system

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I am working on newly construction power plant with frame 9e gas turbine. I want to know how much power is required for mark-vie control system?

That depends--on whether the turbine is running or not.

Typically, when the turbine is at rest (zero speed), and NOT on Cooldown (slowroll or turning gear or whatever method Belfort uses these days), the current draw is approximately 2-3 A @ 125 VDC, or about 250-375 Watts.

Many Mark VIe turbine control panels seem to be shipped with AC-DC converters (sometimes called DACAs) as well as a 125 VDC supply from a battery. The current draw would still be the same, about 250-375 Watts when the turbine was at rest if being supplied by a DACA (or similar AC-DC converter).

Presuming the unit has DLN-I combustors when the turbine is on-line and generating power the current draw increases to somewhere around 5-9 A @ 125 VDC, or about 625-1125 Watts. That's because the Mark VIe provides 125 VDC power (voltage and current) for many solenoid-operated devices when the unit is running, which is the bulk of the increase in current draw. Sometimes, depending on the fuels being burned (if the unit is dual fuel capable) the current drawn may be a little higher (such as during a fuel transfer when both fuel systems are operating), or a little lower (if the auxiliaries/number of solenoids for one fuel is less than for the other). But, these are still pretty good wattage numbers for a typical GE-design Frame 9E heavy duty gas turbine-generator.

These wattage values are for a typical Mark VIe, for a GE-design heavy duty gas turbine and a normal complement of auxiliaries (in other words, not powering additional auxiliaries such as a water treatment system or similar--just the basics normally associated with a GE-design heavy duty gas turbine). This includes only the Mark VIe components and field devices and instruments powered by the Mark VIe (solenoids; servo-valves; LVDTs; RTDs; transmitters (2- and 3-wire 4-20 mA devices; discrete inputs; processors; IONET network switches; flame sensors; and a few very small indicating lights (depending on the application and auxiliaries).

The above wattages do NOT include the AC power for auxiliary motors (pumps; fans; etc.) and such which are not powered by the Mark VIe, but just get RUN signals from the Mark VIe (discrete outputs powered by the individual motor starter control power circuits). It also does NOT include any VLAN (Virtual LAN) network switches used to connect the Mark VIe and HMIs, nor the HMIs (CPUs and monitors and printers).

As an aside, if the 125 VDC battery powering the Mark VIe is pretty much dedicated to the gas turbine-generator and is not used for other control systems like a plant-wide DCS (Distributed Control System), one can usually look at the battery charger voltmeter and as long as the battery voltage is around nominal 125 VDC (say, 130-132 VDC for most 125 VDC systems), and the battery is powering the Mark VIe--and not the DACA--the voltage multiplied by the current shown on the battery charger meters is almost all being consumed by the Mark VIe. Sometimes in this day and age, there are one or more digital protective relays which are also powered by the 125 VDC battery and some of them are drawing as much as 0.5 A--but that number can usually easily be found by looking at the nameplate on the back or side of the relays, and then subtracting it from the battery charger current reading.

Having said all of the above, some sites seem to be using 24 VDC power supplies for the Mark VIe and solenoids and contact input interrogation--and the current drawn/wattages seem to be on the order of 15-25% higher.

The Mark VIe System Guide, GEH-6721, Vol. I, lists some typical wattages estimated by the system designers, usually a little on the high side of real-world values.

Hope this helps!