Rhine UC7051R ceiling fan remote receiver reverse engineer - Page 1
Forum section: electronics / projects

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 11:28:34 am
content: Hi,I'm in the process of repairing/reverse engineering this elderly remote receiver controller fitted into a ceiling fan marked as the 'Omega luxury remote model 5300'. I couldn't find anything similar on the web and so have started this thread to record my progress and as an aid to anyone contemplating something similar.*** Safety *** The circuitties active and +5V power supplies togetherand probing it poses a risk of electric shock and the potential to damage test equipment.First a general description of the controller.The circular receiver is a single sided phenolic PCB marked Rhine UC3051R . The component designators are often under the components and so they have been removed and resoldered to document them. Some components do not have any designators and so I have made them up. There are two Q5s and I have named one Q5A. The RF section is under a tinplate shield.The main IC U2 is a RH7050 probably a custom part made by, or for, Rhine Electronic Co Taiwan. No data sheet or a supplier has been found.The receiver decodes six remote functionsFAN/OFFFOR/REVLIGHT DIMMERHIMEDLOWThe fan motor has two windings (my names A & B) one of which (A) has a permanent series 1.75 uF 350VAC capacitor which I have designated C25. The other motor winding (B) can be reversed electrically by DPDT relay K1. These windings are connected to the mains supply using TRIACS Q3 Q5A and Q11. The motor speed selection is achieved by supplying the motor (both windings) with either full or reduced voltage. The reduction is performed with capacitive droppers C26A and/or C26BIt should be noted that the controller IC U2 will not function without the zero crossing signal (ZCS) on pin 18. This signal is a current limited 20ms square wave of about 6.4V amplitude (probably 5V plus the CMOS IC intrinsic diodes). Since the ZCS is derived from the mains supply it makes it difficult to work on the PCB safely. I rigged up a an external DC supply for the logic and an isolated AC mains supply for the rest of the circuit. A better approach would be to simulate the ZCS (555 timer?) and leave the mains disconnected until it is absolutely necessary. The PCB and motor wiring is short and so I made an extension cable to connect the PCB to the motor using Molex connectors and some seven core cable. The PCB is now on the bench and the fan motor sits on a milk crate under the bench.For those of interest the original fault symptom was that the fan would only creep around. The fan is now working but i don't know what I did to fix it! I didn't realise at first that the ZCS signal was needed and I thought I had damaged the PCB as even the reverse relay wouldn't energise when the PCB was powered from only a DC supply. By the time I learned about the ZCS I had already removed and re-soldered many parts and also re-tuned the receiver and it was too late to diagnose the fix.The serial data line to U2 from the RF section has lots of noise on it. I spent a lot of time trying to figure out why. Save yourself some effort and accept it, as it seems to be normal. The reason it was not working was the missing ZCS signal not the RF.I have attached a couple of photos of a similar receiver much more to come.

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 11:49:11 am
content: Here is the Bill of MaterialsPCB marked RHINE UC7051RPARTS listmiscT1 2413-28T tranformerK1 OMI-SS-212L DPDT relayS1 4WAY DIP SWITCHL1 2 TURN RF INDUCTOR ON BOBBIN (IN RF SECTION)L2 10 TURN RF INDUCTOR ON SLUG (IN RF SECTION)resistorsR1 220R 1/4W (IN RF SECTION)R2 10K 1/4W (IN RF SECTION)R3 1K0 1/4W (IN RF SECTION)R4 10K 1/4W (IN RF SECTION)R5 47R 1/4W (IN RF SECTION)R6 3K3 1/4W (IN RF SECTION)R7 470R 1/4W (IN RF SECTION)R8 3K3 1/4W (IN RF SECTION)R9 10K 1/4W (IN RF SECTION)R10 4K7 1/4W (IN RF SECTION)R11 10K 1/8WR12 10K 1/8WR13 1M0 1/8WR14 15K 1/8WR15 4K7 1/8WR16 1M0 1/8WR17 6K8 1/8WR18 6K8 1/8WR19 6K8 1/8WR20 6K8 1/8WR21 6K8 1/4WR22 82K1/8WR23 1M0 1/8WR24 6K8 1/8WR25 1M0 1/8WR26 missing?R27 160K 1/8WR28 430R 1/4WR29 150R 1/4WR30 150R 1/4WR31 470R 1/4WR32 47R 1/4WR33 3R3 1 WR34 47R 1/8WR35 100K 1/4WR36 2M2 1/8WR37 47R 1/2WR38 47R 1/4WR39 missingR40 100K 1/4WR41 3R3 1 WcapacitorsC1 101 CERAMIC (IN RF SECTION)C2 101 CERAMIC (IN RF SECTION)C3 2.2 CERAMIC (IN RF SECTION)C4 2.7 NPO CERAMIC (IN RF SECTION)C5 2.2 CERAMIC (IN RF SECTION)C6 22 CERAMIC (IN RF SECTION)C7 102 CERAMIC (IN RF SECTION)C8 0.01UF POLY 100VC9 10UF 25V ELECTC10 10UF 25V ELECTC11 105 TANTC12 100UF 16V ELECTROC13 104 MONO BLUEC14 104 CERAMICC15 1000UF 25V ELECTROC16 100UF 16V ELECTROC17 103 CERAMICC18 NOT FITTED LINKED OUTC19 104 400V POLYC20 473 400V POLYC21 473 400V POLYC22 100UF 16V ELECTROC23 561 CERAMICC24 103 CERAMICC25 1.75uF 400WVAC WIREDC26A 1.75 uF 350WVACC26B 3.5uF 350WVACmovsZNR1 SAS391KD07 MOVZNR2 SAS391KD07 MOVsemisQ1 MPSH10 (IN RF SECTION)Q2 MPSH10 (IN RF SECTION)Q3 BTA08600C (ST)Q4 BTA08600C (ST)Q5 8050Q5A T410 600T (ST)TWO Q5's !Q6 78L05Q7 8050Q8 8050Q9 8050Q10 8050Q11 T410 600T (ST)diodesD1 1N4004D2 1N4004D3 1N4004D4 1N4004D5 1N4004D6 1N4004ZD1 NOT FITTED (IN RF SECTION)ICSU1 LM324 dip14U2 RH7050 dip20connectormolex 9waymore to come

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 08:07:10 pm
content: I have attached photos of component side of PCBsome parts were removed before the photo and replaced latermore to come

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 08:10:49 pm
content: I have attached more photos of component side of PCBsome parts were removed before the photo and replaced latermore to come

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 08:13:33 pm
content: I have attached more photos of component side of PCBsome parts were removed before the photo and replaced latermore to come

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 09:35:21 pm
content: Have attached photos of the PCB solder sidemore to come

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 09:39:02 pm
content: Have attached more photos of the PCB solder side

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 10:05:57 pm
content: Added Xray type photos to help track tracingmore to come

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 10:42:24 pm
content: Added Xray type photos to help track tracingmore to come

author: bobdring
author_rank: Contributor
timestamp: January 19, 2018, 10:50:16 pm
content: serial codes used by the remote copied from my other topic

author: bobdring
author_rank: Contributor
timestamp: January 20, 2018, 12:19:28 am
content: First sheet of schematic main connector, power supply and FWD/REV relaymore to come

author: bobdring
author_rank: Contributor
timestamp: January 20, 2018, 03:26:18 am
content: Second sheet of schematic motor connections, REV/FWD switching and fan speed selection

author: bobdring
author_rank: Contributor
timestamp: January 20, 2018, 03:31:00 am
content: Third sheet of schematic lamp dimmer and zero crossing signal

author: bobdring
author_rank: Contributor
timestamp: January 20, 2018, 04:33:05 am
content: Fourth sheet of schematic RF section

author: bobdring
author_rank: Contributor
timestamp: January 20, 2018, 05:26:21 am
content: Fifth sheet of schematic analog signal to digital signal conditioning

author: bobdring
author_rank: Contributor
timestamp: January 20, 2018, 06:32:53 am
content: Sixth and final sheet of schematic RH7050 control IC and support components

author: bobdring
author_rank: Contributor
timestamp: January 21, 2018, 02:21:32 am
content: This is the last post on the project.Documenting the signals on U2 the RH7050 IC.The signal names are of course my own invention and so may be misleading.pin 1,2 & 7 - 0V one or two of these might be unused address code bits set to zero. One is the IC 0Vpin 3,4,5 & 6 REMOTE ADDRESS CODE - An address setting of '1' would be HLLL or switch off,on,on,onpin 8 OSC & 9 OSC OUT - These pins are connected by R29 160K to set the internal oscillator to 100kHz as measured at pin 9pin 10 DATA IN - This is the digital version of the serial data from the RF section. It is pulsed from 5V to ground. There is a lot of pulses on this pin even when the remote transmitter is silent.pin 11 LOW FAN - This 0V signal changes to a 10us 5v positive pulse every 100us when fan LOW pressed. It stays pulsing until FAN OFF or another speed is selectedpin 12 MED FAN - This 0V signal changes to a 10us 5v positive pulse every 100us when fan MED pressed. It stays pulsing until FAN OFF or another speed is selectedpin 13 HI FAN - This 0V signal changes to a 10us 5v positive pulse every 100us when fan HI pressed. It stays pulsing until FAN OFF or another speed is selectedpin 14 NOT KNOWN - This is triangular wave of period 90ms with a low of 2V and a high of 3.5V the wave has a 40ms rise time 50ms and a fall time of. It is still present even without ZCSpin 15 NOT KNOWN - This is a square wave of period 90ms with a low of 0V and a high of 5V. The signal is 50ms high and 40ms low V. It is still still present even without ZCSpin 16 FWD/REV- This is 0V after power on then toggles with FOR/REV between 5V and 0V needs ZCS to be functionalpin 17 5Vpin 18 ZERO CROSSING SIGNAL- The ZCS signal is a 20ms square wave having a low of -0.7V and a high ov 5.7Vpin 19 LIGHT DIMMER- This is a series of 10us pulses every 100us. The 5V pulses start 1.5ms (for a bright light) after ZCS edge and always end 8ms after the ZCS. Holding the DIM button causes the start time to change either dimming or brightening the light. A short press of DIM button selects between light off and the previous light intensity setting.pin 20 POR RESET - This normally hi at 5V it rises slowly (300ms) to 5V after power applied. It is probably the IC reset signalProbing the IC pins often causes it to hang up and so it may be necessary to power off for a while to get it working again. Don't forget the 5V rail is at mains active potential.There, I'm finally out of the rabbit hole... will post if anything new developsI hope that someone finds it useful.Bob