德國重載型實(shí)驗(yàn)室直流電源 PSI 9000 3U系列是一款由微處理器控制的高效實(shí)驗(yàn)室電源，其標(biāo)準(zhǔn)型號配備多種功能和特征。交互式菜單導(dǎo)航功能讓用戶使用起來極其方便、有效?？蓪τ脩艉瓦M(jìn)程文檔進(jìn)行編輯、存儲，以及再次上載，從而改善重復(fù)測試或其它應(yīng)用。為了達(dá)到更大的輸出功率，可配置高達(dá)150kW和42U的機(jī)柜，以便滿足客戶需求。PS德國EA重載型實(shí)驗(yàn)室直流電源I 9360-40 3U多相輸入340...460VAChh效率高達(dá)95.5%hh輸出功率有：0...3.3kW, 0...5kW, 0...6.6kW, 0...10kW,0...15kW, 還可擴(kuò)展至150kWhh輸出電壓：0...40V 至 0...1500Vhh輸出電流：0...30A 至 0...510A還可擴(kuò)展至0...5100Ahh靈活的功率調(diào)整輸出hh各種保護(hù)功能 (OVP, OCP, OPP, OTP)hh直觀的觸摸屏可顯示數(shù)值、狀態(tài)與通知hh能自動(dòng)檢測的遠(yuǎn)程感測端hh隔離模擬接口??通過 0...10V或0...5V電壓可對U / I / P編程??通過 0...10V或0...5V電壓可監(jiān)控U / Ihh真實(shí)函數(shù)發(fā)生器hh光伏方陣模擬功能hh內(nèi)阻模擬與調(diào)整hh用戶配置文檔存儲庫hh溫控風(fēng)扇制冷hh符合SELV標(biāo)準(zhǔn) (EN 60950)的40V產(chǎn)品型號hh配有USB端口hh可選數(shù)字接口模塊hh支持SCPI指令語言帶菜單的圖形顯示器德國EA重載型實(shí)驗(yàn)室直流電源 PSI 9360-40 3U功率本系列所有產(chǎn)品的輸出功率可靈活變化，在低電流時(shí)輸出更高電壓，或在低電壓時(shí)輸出更大電流，都由zui大額定輸出功率來限制。其設(shè)定功率都可調(diào)。因此一臺該儀器能涵蓋大范圍的應(yīng)用領(lǐng)域。 PSI 9360-40 3U輸入本系列所有型號都采用主動(dòng)式PFC功率因數(shù)校正線路，專為在340V - 460V AC三相供電條件下操作而設(shè)計(jì)。而且，根據(jù)客戶需求，可定制15kW型號或用其組建的機(jī)柜組合，適合于588...796V（加上中心點(diǎn)）輸入電壓下操作。直流輸出本系列有多款不同型號，可選擇0...40V和0...1500V輸出電壓，0...40A和0...510A輸出電流，0...3.3kW，0...5kW，0...6.6kW，0...10kW或0...15kW輸出功率的各個(gè)型號。輸出端位于產(chǎn)品后板。保護(hù)功能為保護(hù)連接負(fù)載，可設(shè)定一過壓保護(hù)極限值(OVP)。，以及過流(OCP)與過功率(OPP)保護(hù)極限值。一旦因任何緣故超過了這三個(gè)極限值中的一個(gè)，直流輸出會(huì)被立即切斷，在顯示器和接口端還會(huì)發(fā)出一狀態(tài)信號。本產(chǎn)品還有過溫保護(hù)，如果產(chǎn)品過熱，它會(huì)關(guān)斷直流輸出。遠(yuǎn)程感測端遠(yuǎn)程感測輸入端可直接連到負(fù)載設(shè)備，以補(bǔ)償連線上一定程度的壓降。如果感測輸入端已接到負(fù)載上，本電源會(huì)自動(dòng)檢測并調(diào)整輸出電壓，以確保負(fù)載獲得準(zhǔn)確所需的電壓值。顯示器和控制鍵圖形顯示器清晰顯示輸出電壓/電流/功率的設(shè)定與實(shí)際值。LCD顯示器為觸摸式，用手指即可輕易控制產(chǎn)品所有功能?？捎眯o或者直接從數(shù)字鍵盤輸入來調(diào)節(jié)設(shè)定電壓、電流和、功率或內(nèi)阻（內(nèi)阻模擬）。為避免誤操作，可鎖定所有操作控制鍵。模擬接口產(chǎn)品后面板上裝有一隔離模擬接口。它提供模擬接口輸入腳，接上0V...10V或0V...5V控制電壓，可設(shè)置0...100%的設(shè)定電壓、電流與功率。模擬輸出腳接上0V...10V或0V...5V電壓，可監(jiān)控輸出電壓與電流。此外，還有幾個(gè)輸入腳和輸出腳，可用來控制和監(jiān)控產(chǎn)品狀態(tài)。函數(shù)發(fā)生器本系列產(chǎn)品都具有一可形成如下典型函數(shù)的真實(shí)函數(shù)發(fā)生器，并能將這些函數(shù)曲線應(yīng)用于輸出電壓或輸出電流上。發(fā)生器可通過前板的觸摸屏設(shè)置或某一數(shù)字接口遠(yuǎn)程配置。預(yù)定義函數(shù)會(huì)為用戶提供所有必要的參數(shù)，如Y偏差值，時(shí)間/頻率或幅度，一套完整的配置參數(shù)。除了基于任意發(fā)生器產(chǎn)生的標(biāo)準(zhǔn)函數(shù)外，它還可形成某些復(fù)雜的函數(shù)，并分為多達(dá)100組序列。這些一般用于研發(fā)和生產(chǎn)的測試上。通過前板的USB端口可將這些序列上載使用或存儲于一標(biāo)準(zhǔn)U盤上，這樣方便更換不同的測試序列。下圖是一個(gè)任意發(fā)生器可實(shí)現(xiàn)的由40個(gè)序列組成的復(fù)雜曲線，僅為虛構(gòu)范例?？梢栽诋a(chǎn)品外面或者于產(chǎn)品上創(chuàng)建，然后上載使用或保存：Additionally to the standard functions, which are all based upona so-called arbitrary generator, this base generator is accessiblefor the creation and execution of complex sets of functions,separated into up to 100 sequences. Those can be used fortesting purpose in development and production.The sequences can be loaded from and saved to a standardUSB flash drive via the USB port on the front panel, making iteasy to change between different test sequences.The figure below shows a fictional example of a complex functionof 40 sequences, as it can be realised with the arbitrarygenerator. The function can be created on the device or externallyand then loaded or saved:此外還有一個(gè)XY發(fā)生器，能產(chǎn)生如UI或IU這類的函數(shù)，一般用戶以表格（CSV文檔）形式定義，然后從U盤上上傳。針對光伏相關(guān)的測試，還可形成PV曲線，當(dāng)做用戶可調(diào)關(guān)鍵參數(shù)。甚至通過后續(xù)的固件更新，可安裝更多的曲線特性，供用戶選擇。There is furthermore a XY generator, which is used togenerate other functions like UI or IU, which are definedby the user in form of tables (CSV file) and thenloaded from USB drive.For photovoltaics related tests, a PV curve can be generatedand used from user-adjustable key parameters.Even more characteristics can be installed for userselection by applying future firmware updates.擴(kuò)展功能按照客戶需求可將多個(gè)產(chǎn)品組合成不同的機(jī)柜，zui高可做成42U的機(jī)柜，從而獲得高達(dá)150kW的總功率。如想獲得更高的總輸出功率，可以將PSI 9000 2U與PSI 9000 3U系列某些合適的型號（每臺5-15kW）組合安裝到機(jī)柜內(nèi)。也可見128頁說明。ExtensibilityThe singles units can be combined into various configurationsupon request, also in cabinets of up to 42U,in order to build systems of up to 150kW total power.In order to achieve even higher total power output, thePSI 9000 2U can also be extended in the cabinet withsuitable models from series PSI 9000 3U (5-15kW perunit). See page 128.監(jiān)控特性所有型號都有電壓電流階段監(jiān)控，可以檢測是否過壓或過流，以及欠壓或欠流。監(jiān)測到的結(jié)果會(huì)通過多個(gè)可選方式通知用戶：- 只顯示信號；即使錯(cuò)誤仍存在，也不影響輸出。- 警告一直持續(xù)，消除錯(cuò)誤后必須確認(rèn)該警告信息。- 報(bào)警會(huì)暫時(shí)性地關(guān)斷輸出，也可發(fā)出聲頻信號。Supervision featuresAll models offer supervision features for voltage and currentsteps. The supervision is configurable to monitor voltage orcurrent over- and undershooting. As a reaction, the device cangenerate a notification of selectable type:- Signals are displayed only; even if the fault is still active, withoutaffecting the output.- Warnings remain active and must be acknowledged after thefault is removed.- Alarms will shut off the output instantly and can also be signalledacoustically.選購件? 適合RS232、CANopen、Modbus TCP、Profibus、 Profinet/IO、Devicenet或Ethernet的絕緣數(shù)字接口模塊。接口插槽位于產(chǎn)品后板，方便用戶插上新模塊或替換當(dāng)前模塊。產(chǎn)品會(huì)自動(dòng)檢測接口，并提示需要進(jìn)行少許的配置或不用配置。也可參考122頁。? 高速躍變(僅針對1kW以上產(chǎn)品，見132頁)*? 水冷模塊**Options? Digital interface modules for RS232, CANopen, Modbus TCP,Profibus, Profinet/IO, Devicenet or Ethernet. The interface slotis located on the rear panel, making it easy for the user to plugin a new interface or to replace an existing one. The interfacewill be automatically detected by the device and requires noor only little configuration. See page 122.? High Speed ramping (see page 132) *? Water Cooling **EA-PSI 9000 3U 3.3kW - 150kW重載型實(shí)驗(yàn)室直流電源 / Heavy Duty laboratory DC POW ER SUPPLIEs技術(shù)參數(shù)Technical Data Series EA-PSI 9000 3U / 系列AC輸入電壓Input AC- 電壓- Voltage standard 340...460V, 2ph-3ph- 頻率- Frequency 45...65Hz- 功率因數(shù)- Power factor >0.99DC輸出電壓Output voltage DC-精確度- Accuracy <0.1%- 負(fù)載0-100% 時(shí)的穩(wěn)定度- Stability at 0-100% load <0.05%- 在±10% Δ UIN時(shí)的穩(wěn)定度- Stability at ±10% ΔUIN <0.02%- 負(fù)載從10%-100%調(diào)整需時(shí)- Regulation 10-100% load <2ms- 負(fù)載從10-90%上升需時(shí)- Slew rate 10-90% zui長30ms- 過壓保護(hù)- Overvoltage protection 可調(diào)，范圍為0...110% Unenn / adjustable, 0...110% Unom- 直流端關(guān)閉時(shí)空載放電需時(shí)- No load discharge time on DC off 100% U 針對 / to <60V; 少于10s / less than 10s輸出電流Output current- 精確度- Accuracy <0.2%- 負(fù)載0-100% Δ UA時(shí)的穩(wěn)定度- Stability at 0-100% ΔUOUT <0.15%- 在±10% Δ UIN時(shí)的穩(wěn)定度- Stability at ±10% ΔUIN <0.05%輸出功率Output power- 精確度- Accuracy <1%過壓類別Overvoltage category 2保護(hù)功能Protection OT, OVP, OPP, PF, OCP (2隔離耐壓Isolation- 輸入對外殼- Input to enclosure 2500V DC- 輸入對輸出- Input to output 2500V DC- 輸出對外殼- Output to enclosure DC-對PEzui大耐壓為400V / Max.400V on DC- against PE污染等級Pollution degree 2保護(hù)級別Protection class 1模擬編程 Analog interface 內(nèi)置15-針D-Sub母插 / Built in, 15-pole D-Sub, female-輸入范圍- Input range 0...5V 或 0...10V (可轉(zhuǎn)換) / 0...5V or 0...10V (switchable)- U / I 的精確度- Accuracy U / I 0...10V: <0.2% 0...5V: <0.4%- 可編程分辨率- Programming resolution 見下表 / See tables below串聯(lián)操作Series operation可實(shí)現(xiàn)，任意直流負(fù)對PEzui大有300V DC的電壓轉(zhuǎn)移 / yes, with truemaster-slave with max. potential shift of 400V against PE on any DC minuspole并聯(lián)操作Parallel operation 可實(shí)現(xiàn)，通過真實(shí)主從操作，可連接多達(dá)10臺產(chǎn)品（經(jīng)共享總線) /yes, with true master-slave, up to 10 units (via Share bus)安全標(biāo)準(zhǔn)Standards EN 60950, EN 61326認(rèn)證證書CertificationsEN 61326, IEC 1010, EN 61010EMC通過T?V認(rèn)證，且符合 / EMC T?V approved according toIEC 61000-6-2:2005IEC 61000-6-3:2006 等級 B制冷Cooling 風(fēng)扇，也可選：水冷 / Fan, optional: water工作溫度Operation temperature 0...50°C儲存溫度Storage temperature -20...70°C相對濕度Relative humidity <80%, n.c.使用高度Operation altitude <2000m產(chǎn)品尺寸 (寬x高x長) (1 Dimensions (W H D) (1 19“ 3HE/U 609mm(1 僅為外殼尺寸，非產(chǎn)品整體尺寸 / Enclosure only, not overall(2見第133頁/ See page 133EA-PSI 9000 3U 3.3kW - 150kW重載型實(shí)驗(yàn)室直流電源 / Heavy Duty laboratory DC POW ER SUPPLIEsEA-PSI 9000 3U 3.3kW - 150kW重載型實(shí)驗(yàn)室直流電源 / Heavy Duty laboratory DC POW ER SUPPLIEs
產(chǎn)品型號：EA-PSI 9360-40 3UPSI 9360-40 3U輸入本系列所有型號都采用主動(dòng)式PFC功率因數(shù)校正線路，專為在340V - 460V AC三相供電條件下操作而設(shè)計(jì)。而且，根據(jù)客戶需求，可定制15kW型號或用其組建的機(jī)柜組合，適合于588...796V（加上中心點(diǎn)）輸入電壓下操作。直流輸出本系列有多款不同型號，可選擇0...40V和0...1500V輸出電壓，0...40A和0...510A輸出電流，0...3.3kW，0...5kW，0...6.6kW，0...10kW或0...15kW輸出功率的各個(gè)型號。輸出端位于產(chǎn)品后板。保護(hù)功能為保護(hù)連接負(fù)載，可設(shè)定一過壓保護(hù)極限值(OVP)。，以及過流(OCP)與過功率(OPP)保護(hù)極限值。一旦因任何緣故超過了這三個(gè)極限值中的一個(gè)，直流輸出會(huì)被立即切斷，在顯示器和接口端還會(huì)發(fā)出一狀態(tài)信號。本產(chǎn)品還有過溫保護(hù)，如果產(chǎn)品過熱，它會(huì)關(guān)斷直流輸出。遠(yuǎn)程感測端遠(yuǎn)程感測輸入端可直接連到負(fù)載設(shè)備，以補(bǔ)償連線上一定程度的壓降。如果感測輸入端已接到負(fù)載上，本電源會(huì)自動(dòng)檢測并調(diào)整輸出電壓，以確保負(fù)載獲得準(zhǔn)確所需的電壓值。顯示器和控制鍵圖形顯示器清晰顯示輸出電壓/電流/功率的設(shè)定與實(shí)際值。LCD顯示器為觸摸式，用手指即可輕易控制產(chǎn)品所有功能?？捎眯o或者直接從數(shù)字鍵盤輸入來調(diào)節(jié)設(shè)定電壓、電流和、功率或內(nèi)阻（內(nèi)阻模擬）。為避免誤操作，可鎖定所有操作控制鍵。模擬接口產(chǎn)品后面板上裝有一隔離模擬接口。它提供模擬接口輸入腳，接上0V...10V或0V...5V控制電壓，可設(shè)置0...100%的設(shè)定電壓、電流與功率。模擬輸出腳接上0V...10V或0V...5V電壓，可監(jiān)控輸出電壓與電流。此外，還有幾個(gè)輸入腳和輸出腳，可用來控制和監(jiān)控產(chǎn)品狀態(tài)。
函數(shù)發(fā)生器本系列產(chǎn)品都具有一可形成如下典型函數(shù)的真實(shí)函數(shù)發(fā)生器，并能將這些函數(shù)曲線應(yīng)用于輸出電壓或輸出電流上。發(fā)生器可通過前板的觸摸屏設(shè)置或某一數(shù)字接口遠(yuǎn)程配置。預(yù)定義函數(shù)會(huì)為用戶提供所有必要的參數(shù)，如Y偏差值，時(shí)間/頻率或幅度，一套完整的配置參數(shù)。
除了基于任意發(fā)生器產(chǎn)生的標(biāo)準(zhǔn)函數(shù)外，它還可形成某些復(fù)雜的函數(shù)，并分為多達(dá)100組序列。這些一般用于研發(fā)和生產(chǎn)的測試上。通過前板的USB端口可將這些序列上載使用或存儲于一標(biāo)準(zhǔn)U盤上，這樣方便更換不同的測試序列。下圖是一個(gè)任意發(fā)生器可實(shí)現(xiàn)的由40個(gè)序列組成的復(fù)雜曲線，僅為虛構(gòu)范例?？梢栽诋a(chǎn)品外面或者于產(chǎn)品上創(chuàng)建，然后上載使用或保存：Additionally to the standard functions, which are all based upona so-called arbitrary generator, this base generator is accessiblefor the creation and execution of complex sets of functions,separated into up to 100 sequences. Those can be used fortesting purpose in development and production.The sequences can be loaded from and saved to a standardUSB flash drive via the USB port on the front panel, making iteasy to change between different test sequences.The figure below shows a fictional example of a complex functionof 40 sequences, as it can be realised with the arbitrarygenerator. The function can be created on the device or externallyand then loaded or saved:
此外還有一個(gè)XY發(fā)生器，能產(chǎn)生如UI或IU這類的函數(shù)，一般用戶以表格（CSV文檔）形式定義，然后從U盤上上傳。針對光伏相關(guān)的測試，還可形成PV曲線，當(dāng)做用戶可調(diào)關(guān)鍵參數(shù)。甚至通過后續(xù)的固件更新，可安裝更多的曲線特性，供用戶選擇。There is furthermore a XY generator, which is used togenerate other functions like UI or IU, which are definedby the user in form of tables (CSV file) and thenloaded from USB drive.For photovoltaics related tests, a PV curve can be generatedand used from user-adjustable key parameters.Even more characteristics can be installed for userselection by applying future firmware updates.
擴(kuò)展功能按照客戶需求可將多個(gè)產(chǎn)品組合成不同的機(jī)柜，zui高可做成42U的機(jī)柜，從而獲得高達(dá)150kW的總功率。如想獲得更高的總輸出功率，可以將PSI 9000 2U與PSI 9000 3U系列某些合適的型號（每臺5-15kW）組合安裝到機(jī)柜內(nèi)。也可見128頁說明。ExtensibilityThe singles units can be combined into various configurationsupon request, also in cabinets of up to 42U,in order to build systems of up to 150kW total power.In order to achieve even higher total power output, thePSI 9000 2U can also be extended in the cabinet withsuitable models from series PSI 9000 3U (5-15kW perunit). See page 128.
監(jiān)控特性所有型號都有電壓電流階段監(jiān)控，可以檢測是否過壓或過流，以及欠壓或欠流。監(jiān)測到的結(jié)果會(huì)通過多個(gè)可選方式通知用戶：- 只顯示信號；即使錯(cuò)誤仍存在，也不影響輸出。- 警告一直持續(xù)，消除錯(cuò)誤后必須確認(rèn)該警告信息。- 報(bào)警會(huì)暫時(shí)性地關(guān)斷輸出，也可發(fā)出聲頻信號。Supervision featuresAll models offer supervision features for voltage and currentsteps. The supervision is configurable to monitor voltage orcurrent over- and undershooting. As a reaction, the device cangenerate a notification of selectable type:- Signals are displayed only; even if the fault is still active, withoutaffecting the output.- Warnings remain active and must be acknowledged after thefault is removed.- Alarms will shut off the output instantly and can also be signalledacoustically.選購件? 適合RS232、CANopen、Modbus TCP、Profibus、 Profinet/IO、Devicenet或Ethernet的絕緣數(shù)字接口模塊。接口插槽位于產(chǎn)品后板，方便用戶插上新模塊或替換當(dāng)前模塊。產(chǎn)品會(huì)自動(dòng)檢測接口，并提示需要進(jìn)行少許的配置或不用配置。也可參考122頁。? 高速躍變(僅針對1kW以上產(chǎn)品，見132頁)*? 水冷模塊**Options? Digital interface modules for RS232, CANopen, Modbus TCP,Profibus, Profinet/IO, Devicenet or Ethernet. The interface slotis located on the rear panel, making it easy for the user to plugin a new interface or to replace an existing one. The interfacewill be automatically detected by the device and requires noor only little configuration. See page 122.? High Speed ramping (see page 132) *? Water Cooling **
EA-PSI 9000 3U 3.3kW - 150kW重載型實(shí)驗(yàn)室直流電源 / Heavy Duty laboratory DC POW ER SUPPLIEs技術(shù)參數(shù)Technical Data Series EA-PSI 9000 3U / 系列AC輸入電壓Input AC- 電壓- Voltage standard 340...460V, 2ph-3ph- 頻率- Frequency 45...65Hz- 功率因數(shù)- Power factor >0.99DC輸出電壓Output voltage DC-精確度- Accuracy <0.1%- 負(fù)載0-100% 時(shí)的穩(wěn)定度- Stability at 0-100% load <0.05%- 在±10% Δ UIN時(shí)的穩(wěn)定度- Stability at ±10% ΔUIN <0.02%- 負(fù)載從10%-100%調(diào)整需時(shí)- Regulation 10-100% load <2ms- 負(fù)載從10-90%上升需時(shí)- Slew rate 10-90% zui長30ms- 過壓保護(hù)- Overvoltage protection 可調(diào)，范圍為0...110% Unenn / adjustable, 0...110% Unom- 直流端關(guān)閉時(shí)空載放電需時(shí)- No load discharge time on DC off 100% U 針對 / to <60V; 少于10s / less than 10s輸出電流Output current- 精確度- Accuracy <0.2%- 負(fù)載0-100% Δ UA時(shí)的穩(wěn)定度- Stability at 0-100% ΔUOUT <0.15%- 在±10% Δ UIN時(shí)的穩(wěn)定度- Stability at ±10% ΔUIN <0.05%輸出功率Output power- 精確度- Accuracy <1%過壓類別Overvoltage category 2保護(hù)功能Protection OT, OVP, OPP, PF, OCP (2隔離耐壓Isolation- 輸入對外殼- Input to enclosure 2500V DC- 輸入對輸出- Input to output 2500V DC- 輸出對外殼- Output to enclosure DC-對PEzui大耐壓為400V / Max.400V on DC- against PE污染等級Pollution degree 2保護(hù)級別Protection class 1模擬編程 Analog interface 內(nèi)置15-針D-Sub母插 / Built in, 15-pole D-Sub, female-輸入范圍- Input range 0...5V 或 0...10V (可轉(zhuǎn)換) / 0...5V or 0...10V (switchable)- U / I 的精確度- Accuracy U / I 0...10V: <0.2% 0...5V: <0.4%- 可編程分辨率- Programming resolution 見下表 / See tables below串聯(lián)操作Series operation可實(shí)現(xiàn)，任意直流負(fù)對PEzui大有300V DC的電壓轉(zhuǎn)移 / yes, with truemaster-slave with max. potential shift of 400V against PE on any DC minuspole并聯(lián)操作Parallel operation 可實(shí)現(xiàn)，通過真實(shí)主從操作，可連接多達(dá)10臺產(chǎn)品（經(jīng)共享總線) /yes, with true master-slave, up to 10 units (via Share bus)安全標(biāo)準(zhǔn)Standards EN 60950, EN 61326認(rèn)證證書CertificationsEN 61326, IEC 1010, EN 61010EMC通過T?V認(rèn)證，且符合 / EMC T?V approved according toIEC 61000-6-2:2005IEC 61000-6-3:2006 等級 B制冷Cooling 風(fēng)扇，也可選：水冷 / Fan, optional: water工作溫度Operation temperature 0...50°C儲存溫度Storage temperature -20...70°C相對濕度Relative humidity <80%, n.c.使用高度Operation altitude <2000m產(chǎn)品尺寸 (寬x高x長) (1 Dimensions (W H D) (1 19“ 3HE/U 609mm(1 僅為外殼尺寸，非產(chǎn)品整體尺寸 / Enclosure only, not overall(2見第133頁/ See page 133EA-PSI 9000 3U 3.3kW - 150kW重載型實(shí)驗(yàn)室直流電源 / Heavy Duty laboratory DC POW ER SUPPLIEsEA-PSI 9000 3U 3.3kW - 150kW重載型實(shí)驗(yàn)室直流電源 / Heavy Duty laboratory DC POW ER SUPPLIEs
