Lighting on Erev Shabbos:
When are the Chanukah candles lit? On Erev Shabbos, the Chanukah candles are lit prior to the Shabbos candles. The candles are lit with a blessing even though they are being lit while still day. [The earliest time one can begin to light the Chanukah candles is from Plag Hamincha. Plag Hamincha is 11/4 Zmaniyos hours [75 Zmaniyos minutes] prior to sunset. Some Poskim, however, rule the candles are to be lit near sunset, within a half hour to sunset. Based on this, the custom in Jerusalem is to light the Chanukah candles 25 minutes before sunset, and then immediately afterwards to light Shabbos candles.]
When should Mincha be prayed? Mincha is prayed prior to lighting the Chanukah candles. [In a time of need however one may light the candles prior to Mincha. If one is unable to Daven Mincha with a Minyan prior to candle lighting, it is better to light before Mincha and then Daven Mincha with a Minyan.]
How much oil must the candle contain? On Erev Shabbos one is to place enough oil in the candles for them to remain lit for at least 30 minutes after nightfall. [If one does not have enough oil to last for all the candles, then at least one candle should contain this amount of oil. Preferably, this should be the added candle that corresponds to that night. If one did not place enough oil for any of the candles to last 30 minutes past nightfall, he does not fulfill his obligation.]
Wax candles: One who is using wax candles, must verify that the candles are long enough for them to burn until 30 minutes after nightfall. Thus, practically the candles must be long enough to last a minimum of 70 minutes, if not more, depending on country. If one does not have enough long candles available, then it suffices to have at least one candle which is long enough to last this amount of time.
If the candles extinguished before Shabbos: If the Chanukah candles that were lit Erev Shabbos extinguished before Shabbos had begun, some Poskim rule one is not required to relight the candles. However, other Poskim rule that in such a case, one must relight the candle without a blessing. Practically, one should always relight candles that extinguished before their time, especially on Erev Shabbos. If one has already accepted Shabbos, then he is to ask another person to relight the candles.
On Erev Shabbos Chanukah, one Davens and early Mincha. One lights the Chanukah candles prior to the Shabbos candles, within the time of Plag Hamincha. One is to place enough oil in the candles for them to remain lit for at least 30 minutes after nightfall.
Q&A on when to light
May a wife light the Shabbos candles prior to the husband lighting the Chanukah candles?
Initially, the wife is to only light the Shabbos candles once the Chanukah candles have been lit by her husband. However, in a time of need, she may light the Chanukah candles prior to her husband lighting. She may certainly begin the lighting after her husband has lit one candle, if she is pressed for time.
If a man already lit the Shabbos candles, may he still light the Chanukah candles?
So long as he did not explicitly have in mind to accept Shabbos upon lighting the candles, he may still light the Chanukah candles. [However, he must make sure to accept Shabbos within ten minutes of the initial lighting of the Shabbos candles.]
If a woman already lit Shabbos candles, may she still light the Chanukah candles if no one else is lighting for her?
No [unless she made a Tnaiy]. However, she may ask a Jew who has not yet accepted Shabbos to light the candles for her, having him say the first blessing in her presence while she recites the remaining blessings [of Sheasah Nissim, and Sheheciyanu if this occurred on the first night].
If it is very close to Shabbos and one has not yet Davened Mincha or lit candles, what should he do?
One should first light candles and then Daven Mincha.
Q&A on where to light
If one fears to light the Menorah by the doorway due to children and the like, where is he to light it?
It is to be lit by the window or table.
May one move the Menorah on Shabbos?
Moving the Menorah itself: It is forbidden to move the actual Menorah even after it has extinguished, due to the Muktzah prohibition. It may be moved with an irregularity, just as is the law regarding all Muktzah.
Moving a tray or chair that contains a Menorah: If the tray or chair has become a Basis [see below] then it is Muktzah, and may not be moved unless one uses an irregularity. If the tray or chair is not a Basis, then the tray or chair may be moved together with the Menorah even regularly [without touching the menorah], if one needs the space [as is usually the case when by a doorway]. The tray/chair however may not be moved in a regular fashion simply to prevent the Menorah from getting damaged.
Moving the Menorah while still lit: In the above case [that the tray or chair is not a Basis] one may move the tray or chair gently, even if the Menorah that is on it is still lit, even if it contains oil. However, by an oil candle, this is only allowed if one is able to do so very gently to the point that no oil swerves in the process.
How does one effect that the tray/chair does not become a Basis?
An item which intentionally contains a Muktzah item on top of it, becomes Muktzah over Shabbos just like the item itself. Thus, the chair and tray of the Menorah are Muktzah just as is the law of the Menorah. This status of Muktzah is called a Basis. Nevertheless, there are ways to prevent the chair or tray from becoming a Basis as explained next: A tray or chair does not become a Basis if one places bread [of the Shabbos meal] or another non-Muktzah item [such as a Siddur or Tehillim] of more importance than the flame resting on the tray/table during the entrance of Shabbos [sunset/ candle lighting], and the tray was not manufactured specifically for candles. [Some say this means if the candle tray is not specifically manufactured to be used for candles, then it may have bread [of the Shabbos meal] or another permitted item of more value than the Muktzah items, placed on the tray. Others say that even if the tray was not manufactured for this purpose, but was designated to now be used only for this purpose, then it is always a Basis.]
What is one to do if the tray has become a Basis?
One may only move it with an irregularity [Shinuiy].
 Michaber ibid; Tur 679; Bahag; Darkei Moshe 679; Bach 679; Birkeiy Yosef 679:1; Radbaz 757; Chayeh Adam 154:35; Bigdei Yesha; Kaf Hachaim 679:1; Sefer Haminhagim p. 160 [English]
The reason: As there are opinions who hold that after one has lit the Shabbos candles he has fully accepted Shabbos and thus may no longer light the Chanukah candles. Now, although most Poskim argue on this ruling [regarding men] it is nevertheless proper to first light the Chanukah candles in order to fulfill one’s obligation in accordance to all opinions. [M”B 679:1] Also, according to Kabala, the Chanukah candles are to be lit first. [Ben Ish Chaiy Vayeishev]
Other opinions: Some rule one may light the Shabbos candles first and then light the Chanukah candles. [Tosafus, brought in Tur ibid]
 Rama ibid; Terumos Hadeshen 102; M”A 679:5
 M”A 679:1; Bach; Chayeh Adam 154:35; Peri Chadash 679; Derech Hachaim 1; M”B 679:2; Kaf Hachaim 679:5
 M”B 672:3
This means that one calculates the amount of day hours in the day and then divides that by 12. One then times that by 1.25 hours, which is the number of hours in Plag Hamincha [1 hour and 15 minutes]. Thus, if there are 14 day hours in the day, then each hour when divided into 12 contains 70 minutes, and thus Plag Hamincha would be 1.25 hours times 70 minutes which equals 87.5 minutes prior to sunset.
 Admur in Siddur Hilchos Kerias Shema and 443:4; Gr”a; Ketzos Hashulchan 76:1
Ruling of Admur in Shulchan Aruch: In 263:6 Admur rules that Plag Hamincha is1 hour and 15 minutes before nightfall. This is based on 58:3; 89:1 in which Admur rules the day is from Alos until Tzeis. Likewise, in 261:5 where Admur rules that although one may be stringent to accept Shabbos from 1 and ¼ hours prior to sunset, he may not be lenient to light candles until 1 and ¼ hours prior to nightfall. However, in Admur 443:4 he rules it is counted from sunrise until sunset and so rules Admur in the Siddur.
Other opinions: Some Poskim rule Plag Hamincha is 1.25 Zmaniyos hours prior to nightfall. [M”B 672:3; 679:2; 692:13; Kaf Hachaim 692:29]
 Moadim Uzmanim 2:152 based on Rishonim and Biur Hagra 679
 Luach Eretz Yisrael [Tukichinsky]; Mivakshei Torah ; Moadim Uzmanim 6:84; See Piskeiy Teshuvos 679 footnote 3
 P”M 671 A”A 10; Birkeiy Yosef 679:2; Shaareiy Teshuvah 671; Moed Lekol Chaiy 27:45; Ben Ish Chaiy Vayeishev 20; M”B 679:2; Kaf Hachaim 671:79; Sefer Haminhagim p. 160 [English]
Other customs: Many are accustomed to Daven Mincha after the Chanukah lighting, as it is difficult to arrange a Minyan prior to the Chanukah lighting. [Tzur Yaakov 1:136; See Piskeiy Teshuvos 679:2; Tzur Yaakov 1:136]
 The reason: As the allowance to light the Chanukah candles prior to sunset follows the opinion that from Plag Hamincha is considered night, and thus if one were to afterwards pray Mincha it would contradict to the lighting of the Chanukah candles. [P”M 671 A”A 10; Shaar Hatziyon 679:7; Kaf Hachaim 671:79] Alternatively, the reason is because in the Mikdash, the Karban Tamid was offered prior to lighting the Menorah. [Birkeiy Yosef ibid] See however Tzur Yaakov ibid who answers how these reasons do not contradict the above custom.
 Shaar Hatziyon ibid
 Kitzur Shlah Chanukah; Elya Raba 679; Kaf Hachaim 671:79; There were times that the Rebbe lit Chanukah candles, and then Shabbos candles and only then Davened Mincha with the Minyan. [Hiskashrus 908 footnote 77] See Dvar Moshe 1:15
 Michaber 672:1; P”M 679 A”A 2; Mamar Mordechai 67:2 Machatzis Hashekel 679:2; Chayeh Adam 154:35; Derech Hachaim 4; M”B 679:2; Kaf Hachaim 679:6
 M”B 672:2; Kaf Hachaim 679:6
 Kaf Hachaim ibid
 Chayeh Adam ibid
 M”B 679:2
 As one begins to light the Chanukah candles prior to the Shabbos candles which are lit 18 minutes before sunset, and following sunset until nightfall is approximately 20 minutes, depending on country. In some places the candles must last much longer due to a longer twilight period. Likewise, the earlier one lights the candles before Shabbos, the longer they must last.
 Michaber 673:2
 Taz 673 brought in M”B 672:26
 M”B 672:27; 679:1
 Piskeiy Teshuvos 679:1
 Binyan Shlomo 53; Ben Ish Chaiy Vayeshev based on Kaballah; Piskeiy Teshuvos 679:1
 Ben Ish Chaiy Vayeshev
 Elya Raba 679:2; M”B 679:1; Kaf Hachaim 679:3
Other opinions: Some Poskim rule a man may not light the Chanukah candles after lighting the Shabbos candles. [Taz 679:1]
 Kuntrus Achron 263:2 [brought in Ketzos Hashulchan 74 footnote 26] “a lot less than 15 minutes”; Ketzos Hashulchan 74 footnote 17 “This is approximately 10 minutes” and so writes Piskeiy Teshuvos 263:15 and 32 and Kitzur Dinei Hadlakas Neiros 4:10 and 15; Eretz Tzevi 1:113 says it’s about 8 minutes
 M”A 679:1; Taz 679:1; Chayeh Adam 154:35; M”B 679:1; Kaf Hachaim 679:3; See Admur 263:7
Other opinions: Some Poskim rule a woman may light the Chanukah candles even after lighting the Shabbos candles. [Levush, brought in M”A ibid]
 P”M 679 A”A 1; M”B 679:1; Kaf Hachaim 679:4
 Admur 277:5-6
 Admur 279:1; Michaber 279:1
 Admur 311:14; 308:661-62; Michaber 308:27; 309:3-4; 310:8; 311:8
 Admur 311:14; Michaber 311:8
 Admur 277:3 “A door with an oil candle attached to it may be moved slowly in a way that will not cause the oil to extinguish the flame. 277:5 “If one needs to use the space under the tray then he may move the tray together with the candle which is on it, even if it is made of oil, to any place of his desire.”; Elya Raba 277:14; Elya Zuta 277:3 “It is possible to carry the table slowly in a way that the oil will not swerve, and it is hence not a Pesik Reishei”; Ketzos Hashulchan 112:14
 Admur 309:4; Michaber 309:4; Shabbos 142b;
 Admur 277:6; Michaber 277:3
 Admur 277:6; M”A 277:8; M”B 277:18
 Admur ibid; M”B 277:18; See Piskeiy Teshuvos 277:10; Seemingly this is coming to teach that only the Shabbos Challahs are considered to oneself of more importance then the candles. This contrasts with weekday bread, to which the candles hold more importance in relation to, and thus the table would still remain a basis. This can seemingly answer why in the end of this Halacha Admur mentions that bread also must be of more importance then the flame, as if it is weekday bread then it is not of more importance. [See Ketzos Hashulchan 112 footnote 24; Kitzur Hilchos Shabbos 279 footnote 16]
 One follows whichever is of more importance to oneself, whether due to its value or its necessity. Thus, when Shabbos candles are on one’s table the permitted item placed on one’s table must be of more importance to oneself then is having the light on the table. [Ketzos Hashulchan 112 footnote 24
 Admur 309:4; Based on Michaber 310:8; brought in Admur 310:16
 Admur 279:4; Michaber 279:3
Other opinions: Some Poskim rule that the bread overrides the candle even in such a case. [Kol Bo, brought in Michaber ibid]
 Such as a simple metal or silver tray, or deposable baking pan. Now, although these have been designated to be used for the candles, nevertheless, since they were not specifically made for this use, they can become nullified to the permitted object over the Muktzah object. So is implied from the term used in Admur 279:5 “since the candle is made for the sake of the flame”, and not simply designated. So rules Piskeiy Teshuvos 279:2, however see the new Piskeiy Teshuvos 277:10 brought below.
 P”M 279 A”A 14; Piskeiy Teshuvos 277:10; M”B Dirshu; Igros Moshe 5:22-11
 Admur 308:15; 311:15; 276:9-10; 266:19; 301:39 KU”A 10; So also rules: Mishneh Shabbos 141a; Rosh 3:19 in name of Rabbeinu Yonah; Michaber 311:8; Michaber 308:43; Rama 308:3 regarding blowing; M”A 308:7 regarding kicking Muktzah and 308:41 regarding his question on Michaber regarding sitting on Muktzah; M”B 276:31; 308:13 and 81 and 88; 311:30; 1st opinion in Chayeh Adam; Derech Hachayim; 1st opinion in Aruch Hashulchan 311:20; Kaf Hachaim 311:68 [although brings strict opinion in 69].